The ams_cds script takes me in the cadence window where it says *Error* eval: undefined function - AMS_checkProcessOption
I have started cadence with : ams_cds -tech c35b4 -mode fb in the above query
It seems to me theres something wrong with the tech file here.
ams_cds sounds like a custom script your CAD group put together.
You will need to ask them for help on this.