5.3 version have some extra lines so 5.2 do not know what to do.
If you have a text editor and you delete the line #65, you will be able to go further.
Then you will receive about the same message for every element you have because of an extra row of 0.00000
If you have patience enough, manualy delete one zeroes row per element.
Then you will have to delete the line above the following line:
#$ RIGID
and then the line
#$ EQUIPMNT
And maybe are other things to be investigated.
Short answer: you can not convert 5.3 to 5.2
Regards,
_________________________
Dan