if you have use "skin" car in the MT work (for GPS for example) you have to
get rid of the skins until you finish modification in Challenge edit.
(challenge edit dosent reconize the skin and bug
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)
if you have named your track with these sign $001$o$fff$w ,
you have to rename it to just letters.
example:
$0$wfrozen race, should be just
frozen race
retry and good luck
always make double backup
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trick: zip all your tracks in same folder, then if bug or trouble appear , you got backup not so old
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