The wait is over now, you can download the latest release of Ndless here!
While the biggest change is obviously the support for the CX II models and operating systems, users of later CX calculators (HW revision W and up) can now enjoy a better LCD compatibility mode, with much better application support and performance.
Note that the needed CX (CAS) OS 18.104.22.168 is not directly available from TI’s download pages, only a special “installer” variant which formats the filesystem can be downloaded there. To avoid this needless formatting, you can download just the plain OS from a mirror on tiplanet.org: CX and CX CAS. If you are currently running 4.5.1 or 4.5.2, you need to upgrade to that version of 4.5.3.
The CX II isn’t too different from the later CX I hardware, but there are a few differences which make certain applications misbehave. nespire needs an update to recognize the CX II and nDoom 2+3 needs changes to work around the “Magic VRAM”. Programs which use the
on_key_pressed function (khicas, nTxt) need to be rebuilt with the latest version of the SDK, otherwise they think the On/Home key is perpetually pressed. Those changes are fortunately easy and so updated versions of those programs should be available soon.
Due to changes in the Flash storage layout, support for writing to the NAND directly is intentionally left out, to avoid that incompatible software can brick the calculator by corrupting critical data. Flash and ROM dumping software also needs to be updated to work properly.
Fun fact: the installers for 4.5.3 and 5.2.0 are identical – except for the title text.