There was a similar thread a few months ago. The answer was that, in order to log time in a sim, you EITHER have to be type-rated in the sim you are using, OR under the instruction of someone who is type-rated on the aircraft and is a CAA approved sim instructor.
With FNPT devices, you have to be under the instruction of an approved instructor (eg MCC), and/or the sim ust be approved by the CAA.
Airline-wise, U may count the above sim time in your TT calculation (some do, some don't, I don't think it can cause U any trouble unless of course 50% of your TT is in a sim !!), but NOT for licence issue (eg the 1500 TT rqd for the ATPL).
If validity of sim time is questionned, then why not questionning the validity of taxi time ? If U are queuing for 45mn in Chicago or Miami (happened to me), waiting for the rwy to be cleared, should U still log this as flight time & is it more valuable than a 45mn sim session with engine failures ?
MF