Bleh, can't sleep now XD
Any chance it could be modified to display the current RGB values?
Indeed it could! Replace "Text1.text = Buf" with the following code:
Form1.BackColor = RGB(Asc(Mid$(Buf, 1, 1)), Asc(Mid$(Buf, 2, 1)), Asc(Mid$(Buf, 3, 1)))
Ok, did the changes myself (and a couple of others, including making the program work even if the correct COM-port doesn't exist). If you want to, you can download the new sourcecode for the VB-app from http://zpider.globelan.net/plastbox2/arduinoproxy_vb.rar