1. I would not run it like that!
2. You Could, but i would send it back to Hobby Services
3. No it can not be Tig (Tungsten Inert Gas) Welded, because the tolerances have to be just right!
4. I don't know what your talking about really, but i would not try it!
You can buy parts from towerhobbies parts section here is the link for the wankel parts section: [link=http://www2.towerhobbies.com/cgi-bin/wti0005p?&I=OSMG1400&P=Z]Wankel Parts[/link] Enjoy!