Steps to making a MP game on 3DGS:
1) Update to the latest version, 6.5x.
2) Tell us if you have Standard, Commercial, or Pro
3) Now we can start a serious discussion.

Any version prior to 6.5 will have buggy and/or inefficient network code.
Any version but Pro will have in-complete network code.
Thus updating will not only allay our suspicions that you are using an illegal copy but will also set you on the right path to MP.