Hi ajipes
512mb is very low memory for Nextgen. So slow calculations is not related to memory values in sys.txt. The values in sys.txt are to prevent low memory bugs and freezing in devices.
I think it is better to make new routes. Never copy save folder to new Nextgen.
I see that Boki was answering you while I was typing. Follow his steps for copy saved routes. What he had written is okay.
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