Congradulations on completing CCEMTP! You learned allot of information, and much of it will fade quickly if you don't study. If you're going to challenge the FP-C exam you should do it before that knowledge fades.
FP-C is probably the most difficult academic test for a paramedics. Not only does it require advanced knowledge, but it's comprehensive and encompasses all possible conditions, populations and equipment. To pass this test you will have to review and study for several months and then pay the exam fee.
Keep in mind the the people behind the FP-C exam have developed a ground transport/hospital based critical care paramedic exam CCP-C, which will be available this fall. http://bcctpc.org/
If you decide to take on this challenge I have some advice.
Do not buy the offical study guide, it's full of misprints.
I do recommend Air & Surface Patient Transport: Principles & Practice, by Renee S. Holleran this one of primary texts for the FP-C exam.
Also, Mosby's Emergency & Transport Nursing Examination Review, despite the title it is designed for FP-C review, and was also written by Renee S. Holleran. The included computerized practice exam is misleading because it's content is very different from the actual exam, but it will allow you to practice on a computer based exam.
Read the latest CAMTS standards, and pay special attention to weather minimums. http://www.camts.org/
Review everything, including ACLS, PALS, PEPP, ITLS/BTLS, NRP. Airway management, including all RSI meds, ventilator operation, V:Q issues, Lab values, IABP, Swan-gantz monitoring, and especially gas laws.
I self studied and passed FP-C after CCEMTP, so I do not have an opinion on the professional review courses, but if you can find outlines from those classes they're very helpful.