Am I able to use any other software to communicate with my MultiTest-i or xt stand?

Answer: 

The control, data acquisition and safety features of the Mecmesin MultiTest-i & xt systems have been designed and developed to be used as a complete system along with Mecmesin's ILC loadcells and Emperor™ software.

Therefore the proprietary communication protocol used between the MultiTest-i or xt system and Emperor™ is not available for release to interface with other software / equipment.