gps.txt files are now huge??

Ive been recording GPS data with MapThis .499 (psp290) to make race tracks out of real roads for my favourite racing game.
With .50 the gps.txt files it records are now huge.
For example.
.499 11 minutes was 62k
.50 11 minutes was over 20mb
Has there been a change in the way it records the data?? Is there a setting i need to change??
The larger files are too large for me to do anything with. I usually convert them with gpsvisualizer.com but these new files are too large to upload.
As a result i've had to go back to .499 which i'd rather not do.
Any clues??

I can not play back my recorded gps files.
I assume that "Read gps from file" plays back the recorded data. Is that right?