There is a very hidden, very retro tool to use on star alliance upgrades. Keep in mind only the highest booking classes can be upgraded (usually Y and B).

The only way to get to this tool is to click on your user icon, go to my eurobonus scroll down and there you should find a star alliance upgrade option. Click on it and it will route you to the wonderfully antique SAS star alliance upgrade tool. This is the only way to upgrade with Eurobonus points on Star Alliance flights, none of your ideas work sadly. Good luck.

I think my favourite part of it is the UA booking class requirements to upgrade from Economy to Business. To upgrade from Economy to Business on UA with Eurobonus points you need to be booked in C D or J, which, you guessed it, are Business Class booking classes.