what is new, is there a readme?
You can see the readme or new features/changes/fixes when installing the engine update (the first window that pops up).
Here is the list:
--- Update August 2012 beta 3---
1) Completely changed the tactical interface.
2) Added additional options for the platoons structure and parameters management in the operational phase.
3) Changed some animations for infantry.
4) All game operations is adjusted and remaked.
5) Added support for scripting in the operational phase.
6) Some changes in the operation editor.
7) Changed some of the special effects.
Added new vehicles and weapons: F5E, M2HB, G3 rifle.
9) Adjusted environments, and cockpits visualization.
10) Refined cockpits for the T-62 and M60A1: rounded some elements and reconfigured lighting.
11) Completely redesigned interface in tank mode.
12) The algorithm for shadows rendering and lighting calculation is changed.
13) New commands for platoon, tank and crew control is added.
14) Reconfigured some tracked vehicles.
15) Added tracks in grass from tanks and vehicles.
16) Added ability to perform some tasks in the tank cocpit without the interface.
17) Added new animations in M60A1 tank cockpit.
18) Added a hint what button need to press to cancel a pause mode in the battle.
19) Mini-map is removed in the battle.
20) In realism mode does not display the flags and markers for enemies (in 3D mode).
21) Removed rangefinder lock when the commander's turret on the M60A1 tank is turned.
22) Fixed a bug with the canceling of a short stop command and this command is available from the commanders site.
23) Adjusted algorithm for subtitles and narration issuing.
24) Platoon control options on the gunners site is removed.
25) Added a visual indicator for targets and goals.
26) The ability to request a priority target from the AI commander is now available.
27) Added the button to send permission to open fire on the specified target.
28) Added support for automatic setup gun direction from the AI commander on requested target (for T-62 tank).
29) Added lock for measuring range for the AI commander, if target is out of rangefinder view (for M60 tank).
30) Added feedback and indication for obstacles in the path of the tank, for AI driver.
31) Added indication that the range measurement process continues, as well as the inability to range measure.
32) The targeting algorithm is changed.
33) The ability to switch the tempo of fire for machine guns.
34) Added to the sight reticles for the T-62 from Vadifon.
35) The ability to control the mode of target selection (one or different targets) for the tank platoon or users tank.
36) Added a command to align the gun on the hull of the tank.
37) Added the ability to specify the range for the gunner in binoculars mode.
38) Fixed a number of glitches and bugs.
39) Added a mod stencil from Krabb.
28) Added weapons overheating and accounting interchangeable barrels and cooling type.
29) Added indicator of the presence and operability for the radio.
30) Fixed bug with "silent" repairing tracks.
31) Fixed a bug with empty message panel after savegame loading.
32) Fixed a bug with the "braking" a column formation by weary soldiers.
33) The algorithm of the calculation of fatigue and rest soldiers is changed.
34) Added surface rounding for the fumes and dust.
35) Change the density for the some special effects.
36) Fixed a bug with the "quick turn" of the head after the head mechanisms is damaged.
37) Added a faster shaders for dust and smoke in the simple shaders mode.
38) Adjusted algorithm for throwing grenades at a short distance.
39) Adjusted form for fumes from the fires.
40) Fixed a bug with the size of craters for some types of ammunition.
41) Added indication of the direction and strength for the wind in combat mode.
42) Adjusted algorithm of target detection and recognition.
43) Removed confirmation dialog to restart updater during the installation of the patch.
44) Added ZIP extension in patch selection dialog.
45) Removed a bug with visibility in the broken sight when the light filter is on.
46) If hold down the Shift key, then all commands that are given through the direct control affects only to the user tank.
47) Fixed bug with the bright colors of in EOC sight with unchecked realistic view setting.
48) Fixed bug with animation for soldiers planted over armored vehicles.
Changes for "beta3" are from 30) onwards I think.
the new Beta3 Patch show ingame V 5.81 1983 aug 12b2
Yes, everything is ok - the patch is installed succesfully. Don't ask me why, I don't know their patch naming system.