That would be the default for the X10 series unless a CF card is used.
Might be wrong but is it possible that your bootloader is below 5.5112?
I noticed that on some device the never V9 Navcores won't work properly with very old bootloaders.
If your booloader is still the original 4.86 than I suggest to update it.

But since you already have the installer at hand, try the GO version again,
but before you start yout TT edit the file "reskin" in the folder "skins"
the entries are seperated by a " ; " ,
your reskin file should look like this:
25-GO x30;25-GO x30;37-GO x50;37-GO x50;18-GO x20;24-GO x40
Replace with this
24-GO x40;24-GO x40;25-GO x30;37-GO x50;37-GO x50;18-GO x20
Now you TT should start in X40 emulation.

If still no luck see if the Memory Boost version for the 32mb models starts on your TT.