You can expand your K750’s SMS Memory very easy like it is written here:
1. Browse to the folder /ifs/settings/messaging/ with FAR Manager
2. select pref_store.txt an hit F4
3. Just change „/smsdata“ in „/tpa“
4. Save the changes
5. go back to „root“ like mb-new description and shutdown the loader
6. Now restart your Phone and be happy
For me it worked perfekt!
AFAIK it’s the first solution to expand SMS Memory without special service cables, you only need DCU-60.