I purchased a CoreGrafx II & Super CD-ROM2 combo from a Japanese seller on eBay and it arrived today here in the USA. It was packaged extremely well and both units were in really good shape, unfortunately something did not survive the trip. The CoreGrafx was modded to play both PCE and TG Hucards; it has a toggle switch near the controller port to switch between the two modes. When I unwrapped the unit I could tell something was wrong because the toggle switch was flopping around and there was something rattling inside. The toggle switch is clearly broken as it moves freely and even disappears into the CoreGrafx.
Based on the light being off, the CoreGrafx is in PCE mode. Sadly I don't have any PCE Hucards to confirm it works with them. With a TG huey the system displays a blank white screen. On the bright side, the Super CD-ROM2 appears to work fine. Well, as far as I can tell it does. I don't have any SCD games either to fully test it. But it does load and play music CDs. Below is a video showing the broken toggle switch and a pic showing how it should work.
I've contacted the seller to see what can be done. Instead of returning the unit to Japan to be repaired and then shipped back to me, I proposed for the seller to refund some of the money. Then I'll look into replacing the switch myself. I'll keep you guys updated.
Video of broken toggle switch:
Closeup pic of toggle switch and LED: