Check if the configurations are being stored on the vpxd.cfg file. Example:
<vpxd>
<das>
<slotCpuMinMHz>256</slotCpuMinMHz>
</das>
</vpxd>
Try also to leave all in case-sensitive strings. This file should be stored at:
%ALLUSERPROFILE%\Application Data\VMware\VMware VirtualCenter\vpxd.cfg