Ok, so they made some more changes in the buildroot configuration.
I'll check that, but it needs ~2 hours to compile (Or I bypass make clean)
Use http://tiplanet.org/nspire-linux-builds/xconfig_20130112_1412.tar.bz2 instead.
that's my version.
Tip: Don't extract it over / or you'll break your system (own experience)

BTW: directfb should still work. "df_window" is a good example for touchpad and graphics.

You just corrupted your nand/filesystem/bad block table.

Nope, you didn't xD Sometimes I only need to reboot, but most times I have to run NAND tests in diag mode..

To get into diagnostics you have to press Esc+Menu+- while pressing reset on the back.

Edit: Figured it out, it passed the NAND test...weird

Yes, it is weird. But sadly we can't fix it as we don't know the cause.

Does X work now and could you move the cursor with the mouse?
I could only test it on my device.

I tested your image and it works perfectly

Except it makes your calculator refuse to boot in 80% of all cases xD

No problems, you can build your own rootfs. I posted a tutorial on configuring somewhere in the other thread, too lazy to search now.

You can also use some other distribution, like opensuse or debian, as long as it runs on armv5.

Nope, the patch is for the kernel

Yeah, but keep in mind that the Nspire series, despite being the most powerful group of calculators on the market, is a wimp in terms of raw CPU power and available RAM.
Compilation and linking "complex" C++ code (just include several Qt headers, in a simple C++ program with very few LOC) easily takes hundreds of megabytes of RAM and 2-3 seconds on '2011-'2012 x86_64 computers. The Nspire's CPU is nearly two orders of magnitude slower than the x86_64 computer, and it has two orders of magnitude less RAM...