The problem with testing package is resolved.
Well, it turned out that there was no problem at all
You can now freely use tdm_update to get new beta package.
In fact, it is advised to run tdm_update now just to be safe.
The new beta release beta207-03 is available.
The summary of changes is available here.
After update, please make sure that cvars are: r_useFBO 1 and r_fboSharedDepth 0
The problem with heatHaze materials and depth-reading material stages is resolved.
Adding maskDepth keyword to such materials is no longer necessary (is it was in 2.05). The keyword has been removed from all corresponding stock shaders.
Please test various heatHaze/translucent/postprocessing materials with the new beta, with antialiasing off (and also test a bit with AA on).
Another thing which needs serious testing is the Linux build.
Whoever runs native Linux build, please check how Alt+tabbing works in various modes (Windowed/Fullscreen).
One known issue is that some Linuxes has "Alt" as a hotkey, which somewhat messes with Alt-tabbing.
P.S. And if you are feeling lucky, you can try to get beta207-03 via tdmupdate_tdmsync prototype.
It greatly reduces download size for beta207-02 to beta207-03 update.
Just make sure to configure tdm_mirrors.txt properly and enable two checkboxes if you do so.