You only need to put an incandescent in one of the worst spots and see if the problem goes away.

The two flasher issues are not likely to be related. On the flasher that now doesn't work I would suspect a cold solder joint (as dsuperbee suggested) or a blown trace/through-hole. Post a close-up, in-focus picture of the work done.

Just noticed this. Disconnect the robby the robot mod and see what happens.

Q91-Q98 are TIP107's in a TO220 package, which means the left lead is base (rather than the middle leg). Here's the datasheet.

http://www.st.com/content/ccc/resource/technical/document/datasheet/26/ce/01/f7/11/e9/46/92/CD00001234.pdf/files/CD00001234.pdf/jcr:content/translations/en.CD00001234.pdf

Some of the online information is incorrect in regards to testing TO220 packages and uses the middle lead as a reference rather than the left lead. Here's the proper way to test.

PNP transistors, left lead is base (i.e. - TIP36C and TIP42)*
Put the DMM's black lead on the left leg of the transistor.
Test to the middle leg and the right leg with the red lead.
You should get a reading between .3 - .9 volts on each (the two reading should be about the same).
Put the red lead on the left leg of the transistor.
Test to the middle leg and the right leg with the black lead.
Your DMM should read open on each.
Test across the middle and right legs, you should get an open reading.
Reverse leads on the middle and right legs, you should get an open reading.

TIP1-7's are also Darlington transistors and have internal resistors and a diode that can cause odd readings. The best thing to do is check them vs a know good transistor (in-circuit since that will also affect readings). It is unlikely they are all bad so if they all test them same I would presume they are good.