Same problem with build 536.
Windows 7 Ultimate (6.1.7600) 32-bit
eBoostr 4.0 build 536
ASUS P4C800 Deluxe
DDR 4x1Gb
Info in "Configure Devices" says:
"794 MB available of 3069 MB total" -- that's right
When "Enable use of hidden system memory" checkbox is ticked, information changed to:
"61958 MB available of 64253 MB total (61184 MB unmanaged)" -- this is pretty wrong
Pressing "OK" caused computer to freeze totally (mouse cursor is not moving). Since reset, computer does not boot normally, falling to infinite boot loop. Only workaround is System Restore or renaming/deleting %SystemRoot%\system32\drivers\eBoost.sys
Maybe something like "Test" button would be pretty useful so user will have a chance to test new settings with no fear to screw up his entire system.
P. S. Fell free to contact me. I'm glad to do some tests for you. And I'm handy enough with windbg.