I tried to replicate this issue on my Mk4, but it keeps to be totally stable for now.

- which version of NavTweak did You use
I did v2.7
- which modification besides POISoN pathing did You do?
my is: color change, just 9kB splash screen, sky change, CZ translation
- which map scale do You use when it reboots?
my: all where camera's picture is visible (100m to 2km)
- how much POIs do You have added to map?
my: just cca 1500 POIs
- do You use DVD or CD version of map?
my: just DVD
- how far is the destination entered?
I tried up to 1200km.
- which part of the world You are in (e.g. because of POIs comparation...)?
Central Europe

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Despite driving Xs´smaller brother E46/3, still having a lot in common ...