MysterySword Wrote:Hmm... so would either method keep semi-transparency if a GIM that wouldn't normally convert had it? 32-bit BMPs are capable of semi-transparency, right?

Yeah they are, though I'm not sure if GimConv keeps the transparency specified in 32-bit BMPs.  If not, you'll have to manually convert to PNG unfortunately.
Or use RCO Editor to generate the GIMs and never use conversion with Rcomage.