Yummy. I am glad for you!
I just checked the script in an editor. It seems, that, when removing the graphical arguments xdialog behaves like dialog. But I am new to this, so I am not 100% on this. But you know this already better than me, I guess.
As I see, it does not copy any AmigaOS files. That would mean, that all I need to do is to setup the e-uae and Amikit stuff and boot. Then AmiKit will launch a installer on the Amiga side?!
Also I wonder, why you set uo the RAM the way it is being set up in the .uaerc file. You use slow- and fast-ram while you leave 1MB for chip only, however, for Z3 you assign 128MB, despite mentioning in the Linux guide, that anything above 32MB Z3 RAM breaks JIT. Has this changed?
Shouldn't 64MB for OS3.9 suffice by large? And 16MB of VGA RAM should suffice, at least for displays, that us mortals own?! I had no problem with my old AmigaForever stuff using only 8MB of VGA RAM in fullscreen at uaegfx/1280x800/24bit.
Also it seems, that the JIT got used with 2MB chip, 0 slow, 0 fast, 64MB Z3 RAM. I have set "direct after P96" for all three memory access variants.