Shiron's Tool works 100%:

Together with using alternating save game slots in Gothic 3 you'll never lose a savegame again.

Use Shirons Tool to bypass the "smartheap - out of memory"-bug completely.
This tools is a Gothic Starter and it reserves some memory (choose 100 MB).
When the error occurs

a) change to the desktop via Alt-Tab
b) release the reserved 100 MB with the button "Speicher wieder freigeben"
c) push the "retry" button on the smartheap requester
d) Alt-tab back
e) Gothic can finish the save game process.
f) At last close gothic and start again.

Description (german)
http://forum.worldofplayers.de/forum…7&#post2507867

short:
Unpack "G3Starter.exe" and "memTool.dll" in your Gothic 3 folder and make desktop link to "G3Starter.exe" then start it.

Download:
http://rapidshare.com/files/32446515/Shiron.zip