Thank you, that sounds really promising. Unfortunately it has no effect for me.
I quit Virtuoso, added exactly these lines (in front of everything else) to the .cdsenv file in my home directory (separated with tabs):
asimenv.window x int 1024
asimenv.window y int 768
But once I start virtuoso again, the windows popup exactly at thesame spots: Secondary monitor, top-left (0,0).
Is there anything special to consider? tabs vs. spaces? Location of the file? Location within the file? Etc.