I just had a look on the internet and it seems that no plugin works on the carminat (at least a a plugin integrated in navigation software).
So there is no hope with this method...
Can you tell me what is the OS version on your tomtom (you can see it on the informations screen : click on the satellite reception icon in the lower right of the map view, then click the 'version' button again in the lower right.)
The ttsystem file is a file made of the Linux Kernel and the RFS (root file system). It can be built with this tool : http://www.opentom.org/Mkttimage
In the standalone version of Tomplayer, i provide my own build of the kernel and boot scripts to directly launch tomplayer.
If i am able to build a kernel that boots on your device then i am likely to be able to provide a working tomplayer (as a standalone app), that's why i am asking for your OS version : to check if this version is available on Tomtom GPL download page and build a new ttsystem file...