Hi Rayne,
I am certain you would be able to use all the essential oils, as I said before apart from the unsafe list. I was a student member with the FHT 10 years ago, perhaps this is what you mean?... When you are training (and covered with student insurance) you can only use the oils specified in your course (back then it was around 16 oils, now it's 40), once qualified you can use all the oils you want (again not the unsafe list).
Yes research the oils you want to use by all means, there is loads of information on the net, all good companies like tisserand or essentially oils, quinessence will have detailed information on each oil, including contra-indications and precautions.
I hope this answers your question, if you are still unsure you could always ring the FHT (or whoever you are insured with) and double check, but I'd be surprised if they said you couldn't use oils you haven't studied with the VTCT.
I am also VTCT qualified and I use many more oils than the currently updated VTCT 40 list.
Shout if you need any further help!
Caroline