We have been asked several times about TightVNC 1.3dev6 installer and if it will be possible to install this version of TightVNC using upcoming VNC Manager 2.5.0 build.
The reply was is that we will way till TightVNC 1.3 will be officially released and only then it will be included in VNC Deployment Wizard. But since seems that it will take age to way for TightVNC 1.3 release we have adjusted our plans a bit.

We no have first build of TightVNC 1.3dev6 installer ready. It needs some bug fixing and testing but in general it's pretty much ready.
This installer will be included in VNC Manager 2.5.1, which will be released shortly after 2.5.0 release. Feature set for 2.5.0 release is frozen now, we are working on a final bug fixes and that's all. Build 2.5.0 will be released right after a New Year holidays.