Sorry to drag up and old post but I've had quite a few PM's (including one yesterday) asking about the mod required to use a switcher with EDOT and have the fluorescents work so I thought I'd just post it here for anyone else who might need it in future. I got mine working with a Wizzies Workshop MCR adapter but I'd assume the same would hold true for the ArcadeShop one now. YMMV.
So first things first. Make sure you have a powerful switch mode power supply. EDOT has a lot of pcbs and draws a lot of power especially over old wiring, I can't recall the exact specs of the one I used but use something with some guts, the install instructions for the adapter have some useful recommendations iirc.
To install it, I connected up the adapter as you would for any other MCR game but added some extra wires from the switcher for the -5v supply needed for the Squawk and Talk board. I added a 3 pin connector and plugged it in to the original wiring that comes out of the -5 auxiliary PSU. With this the game PCB's will run fine and you should have all the sounds including Sark chatting away but the flashing fluorescents won't work.
For the flashing problem, it took me a very long time to figure it out and find. Basically the Flashing Fluorescent PCB seems to still need a strange output from the original power supply which a switch mode PSU isn't ever going to be able to generate (as far as I can tell). It's not very well documented on the schematics hence to time it took to find it. You need to make sure that pin 14 of the power supply board (CONN 4 15 pins on the schematics) is still connected. This eventually goes into pin 10 on the Flasher Control PCB. On the main power wiring diagram in the schematics it's just noted as "S", which isn't very helpful. On the Flashing Fluorescent schematic pin 10 is shown as "A.C Sync" and is used as an input to a 4050 IC. I believe that it's used to control the timing of the pulse to the fluorescent lamps so that it's in sync with the AC phase, I'd guess it's to time when the AC is positive or something like that. I used an extractor tool on the loom (so that it can go back as it was if needed) and just plugged that single wire into Pin 14 and voila the lights are flashing again.
I'd love to have the time to work out what this A.C Sync is and how to replace it with a switch mode supply but time is too short these days.
Anyway, hope it's useful to someone and just to reiterate - this worked for me. YMMV
Dan