Welcome to the club. Here are a few quick answers.

1.) Not that I've heard. I've never found it to be necessary. Perhaps because...
2.) It's absolutely worth it and will indeed improve your blacks. (You can tweak the brightness/contrast much more effectively once it is in place.)
4.) Yes, you can buy a usb to serial adapter and a null modem cable. Getting the old update software to work with whatever version of windows you are using well enough to recognize the usb/serial port can be tricky, so your mileage may vary.

I believe Rob Anthony offers a Pub Card rental service which is by far the easiest way to update your machine if you don't have an older computer setup to do it via serial.

http://www.lockwhenlit.com/products.htm

It does take a hefty deposit, but after all is said and done it's $30 to rent the card.

You can buy replacement ramp flaps. I think they are fairly cheap.

http://bayareaamusements.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GS-RFM01-15141

I haven't tried the update via usb to serial, but have done it via serial. I do believe others have done it with a usb to serial adapter successfully though.

You can probably fill the gaps in with something. Whatever you use I would suggest isn't permanent, as at some point you may need to replace the aging monitor with an LCD or something like others have done.

I can answer number 6.......
Mine had the same issue. I laid a black mask from an arcade monitor around it and problem was solved. I assume mine sat like that due to it having a kortek monitor in it (originals were wg or ducscan (excuse spelling)). Video amp is amazing btw. I just put it into my machine!

With #6 I had lots of light leaking through around the TV. I just placed some thick foam that i got from home depot that had adhesive on one side around the TV and it blocked out all the light. Looks so much better.

I do need to get the VGA amplifier and try that out.

you can purchase a pub card from pinball spare parts australia for about $70 (sell it on ebay after you're done and you'll probably re-coup just about all of your initial investment

you'll need a drill to remove the rivets on the original skip ramp flap and a rivet press to properly rivet the new flap in place. be sure to order a pair of 1/8" diameter x 1/8" nickel plated rivets (link for reference)
http://www.marcospecialties.com/pinball-parts/07-6688-16N

be sure to note the orientation of the original ramp flap where it's attached to the bracket. the flap itself should be concave when rests so that the edges seat nice and tight against the playfield when it is in the "down" position.

the nice part is that removing just 2 bolts from underneath the playfield, frees the ramp flap and the bracket completely.

there is a stainless version of the ramp flap, however since it is silver in color (and not black anodized like the original), I would avoid it.

if you don't have a way to replace the flap yourself, I have a couple of extras and the associated brackets. I would be more than willing to work out a deal where I send you new set (already riveted) and you send me your original with the damaged flap

my mistake, I should have stated convex. it should be applied so that from an angle it appears like this:

ramp flap -> ( | <- playfield

there is a subtle bend in the spring steel that is used for the ramp flap so that the edges of the ramp flap meet the playfield and the center of the ramp has a slight arc between them (which would keep a ball from resting on the ramp)

if you'd like, I can take a few photos of the new one that I just did for my machine (my original ramp had 'cuts' on both the left and right edges, approximately at the midway point of the ramp (probably from taking hits from pinballs [especially during multi-ball])

I remember reading something in the part description about a defective cable causing audio static

see link below:
http://www.pinballlife.com/index.php?p=product&id=781

I would be interested in a answer to the audio also. I just picked up a Star Wars episode 1 with a clean bright CRT still installed - my subtle static seems to coincide with the image on the screen - meaning when the screen is displaying images of characters, the static is gone, but when the screen rolls through animations, the static comes back, coinciding with the animation.... I'm thinking its the CRT....loose yoke or something???

I didn't remove any bulbs, but I did change to mostly red LEDs on lamps behind the screen projection which for me balances the ability to see the ball behind the screen while minimizing inteference with the projected image. YMMV

I just found this - not sure we can link to external sites so did a copy & paste with my Iphone.

Static Sound Disturbance (German:Knistern):
(M.Wiest, Tom Uban)

A lot of Pinball2000 owners have problem with static sounds disturbing the pinball 2000 great sound, especially in gameover mode. Tom Uban and Martin Wiest finally found the solution for it. Read the infos below:

From Tom Uban:

Hi, Well it is interesting that your removal of the cable tie on the cable helped out the problem. The reason for the static (I am told) is that there is cross talk in the signals driving the amplifier from the PRISM. While there was an early change to add the inline resistors on some of the signals, it appears that all of the boards I have seen (and which you describe) have the resistor change. I guess that the change was made fairly early and that very few of the old version PRISM boards made it into the field. The second change (which I significantly easier to make) which affects the static problem is to cut all of the tie-wraps on the PRISM-amplifier cable and let the wires separate. This reduces the cross talk and thus the static. I did this on my RFM, which was having the static problem, and it has mostly gone away. Give it a try... --tom

From Martin Wiest:
Hello Tom.

BINGO ! I removed all the cable ties of that cable in my Ep1 and all statics are dissapeared!! Great success. Thanks a lot for your help. Martin

No - the GI back there turns off during most modes & only lights up when the ball is back there.

Did the VGA amplifier help the content portion of the video look better, brighter? I have played with the board that comes with the montior, I don't remember as to your particular issue since I haven't noticed too bad of a problem with dark blacks.

Kevlar:
which monitor do you have in your RFM? and did you remove the resistor for the red gun?

For blurry, focus is on the flyback fyi. Right above G2. You must balance G2, picture and brightness for good black levels. G2 is probably too high with the amp in fyi.

Also a quick note on blurry. I had the playfield glass upside down and had lots of blurry (doubling of characters), I know they have a coating on it and apparently, one side up is better. Try it it a couple different orientations, even flipped over.

Fly back transformer is the large transformer that puts out the high voltage to the tube. It has the anode lead going directly into the tube. There are two controls on the back of the transformer. The top is focus and the bottom is G2. Both needed adjustment after the amp. The top control on most is focus and the bottom is G2 (screen intensity for all basic purposes). Contrast/picture, brightness and G2 all work together for picture brightness / black level. I repair TVs for a living so that aspect is kind of my specialty.

The transformer is on the monitor chassis (the circuit board) that sits under the monitor horizontally. The neck board is the board on the back that mounts vertically to the back of the tube. Bu the transformer will likely be the largest piece (black in color) on the chassis board. As mentioned above, it carries the larger thick (anode) wire to the top of the tube. And don't touch it! On or off unless you know how to dissipate any potential left in that wire.

Generally these pin2k's have or left Williams with either the Ducksan or Wells Gardner monitor.