Okay.. well, I answered a lot of my own questions today.
First of all, the power supply is bad, that is why it works without a
floppy but not with. I know this because I was given two IIgs systems and
the other one works. So I swapped the power supplies and the problem
follows the power supply, not the system.
Secondly, I get color once the OS starts loading, but for some reason the
control panel wouldn't give color. Of course, I was surprised to see that
same nasty color-phase-shift problem that older Apple's suffered from. I
thought surely by the time the IIgs was out Apple would have fixed that
problem. That is such a disappointment. I'll try building that adapter to
connect to my Amiga monitor's RGB input and I can pray that maybe it will
look better there.