Hi, for the course the top5 EAs are replaced monthly and so there is no need to buy again, just download the new ones each month. As to first question, how long have they been running for, they will run on any account and do not require any license or other such hurdle. It could just be that they need more time to find an entry.
Also in finding good results I have put up two recent threads that may assist:
Many Prop Firm Challenges Passed with EA Studio!
Many Prop Firm Challenges Passed with EA Studio!
Hope these are helpful and feel free to ask any more questions.
Cheers,
Sam