All of our multi core machines have 4 Gb and the minimum ram on the others is 2 Gb.
Parameters
-Duser.home=f:\java-apps\projectlibre-162 -Xms128m -Xmx768m -jar projectlibre.jar
If you have 2 or 4Gb memory then you don't have problems with -Xmx768m, there is enough room. VIRTUALADDRESSLIMIT is an important item in it. For Java however you need physical memory. May be its time to change motherboard, its over 10 years now, but still functional and okay up to now.
You can make your own icon with pictogram editor, its somewhere in your OS/2 installation part. I regularly use wptools checkini with /c. But thanks for the hints, will try it.