On a TM-TWIN-OE running ViX 3.0 I found that I could not get Mgcamd v1.35 or v1.35a to show on Softcam menu after install.
However, I found one on these forums (v1.38_ViX I think) that did install correctly and show in Softcam menu.
As others have found, the config file had to be modified from 'auto detect' the STB to '06' but you only have to do this once.