Bug reports without an attached log file are usually useless.
Re: Update button text
OK, you are probably right.
Update button text
In the update dialog that appears ("Check for Updates - WinSCP"), we have the new version number, the changelog and three button - from right to left: Help, Close and Upgrade.
"Upgrade" is generally used for purchasing, not for downloading new versions.
Isn't it better to use "Update"?