Just tried to upgrade Lazarus 1.6.2 x64 to 1.6.4 x64 on Linux Mint 17 LTS, 64-bit.
Installation seems to go OK but on launch I briefly get the splashscreen with the cheetah and it says "1.6.4" at the bottom and then I get the usual new installation screen but it says "Welcome to Lazarus 1.6.2". Then there is a red exclamation mark in the left next to "Lazarus" and the messages is "Warning : wrong version in ide/version.inc: 1.6.4" and the selected path in the field above is "/usr/share/lazarus/1.6.4"
So I tried uninstalling everything using
> sudo dpkg --remove packagenames
and tried re-installing fpc, fpc-src and lazarus-project. Same problem. If I click OK to the "Start IDE" button I get a warning that I'll see lots of error, and I indeed do so!
Is it just me or is there a trick or something to get past the problem?