I so love the Indivisions in both my systems... nothing like the 21st century convenience of being able to make use of any modern monitor or projector (for such a reasonable price), that I'm going to try chiming in here one more time.
How about this? Get an Indivision, hook the 1084 to the Amiga's 23-pin output, and then use a VGA-to-composite converter on the HD15 output of the Indivision? (since I see you're using an A500. The newer models of Indivision for A1200/4000 have DVI or HDMI output.)
A quick google search for "VGA to composite adapter" yields hundreds of products. I'd buy from somewhere like Amazon that has a liberal return policy, in case you wind up with one that for whatever reason doesn't work with the VGA output on the Indivision. You could use this if you want to do screen capture on a PC, alternatively I've seen some PC video capture cards that have a direct HD15 (VGA) input for capturing video in higher quality.
Or, as a last "suggestion", get a TV that has VGA input? I know, I know, not everyone wants to go out and buy a new TV, just saying because this was kind of a requirement for me when I went TV shopping, haha.
Good luck with your project!
