Hi Alan, yes I would have expected it to be easier to pass the minimum trade count acceptance criteria on M15.
First are you absolutely sure of these three things:
1. The EA studio settings are identical except for the timeframe
2. This is for the same symbol
3. That you have all the bars for the full 5 year days range for M15 and there are no gaps (use the check in the data statistics to confirm this)
Once you have confirmed these I will be able to help more.