Hi Swan,
I'm sure if someone had a solution to your problem they would've posted.
I have found on my own computer that some games just refuse to work on my PC despite the fact that everyone else seems to have no problems (It's not because I am a "pc novice" either). There have been a few games I just uninstall and announce that game just "wasn't for me".
Just be careful with your tone as it comes across as very demanding and agressive. The moderators at this site are volunteer users who do not have any additional access to support resources than you have. We download the giveaways the same as everyone else and install them on our home computers using the same activation programs and serial numbers etc.
At the end of the day, the moderators do not have all (or even "most") of the answers. Remember the giveaways are offered without any support, and you should consider yourself lucky to receive whatever help you can get (for free).
Likewise other users (like yourself) are welcome to offer insights or opinions to assist with solving other problems or making suggestions of worthwhile (usually freeware) software that others may benefit from knowing about.
Anyway - I agreed with Lees' observation that the errors you described COULD HAVE been caused by the program being open (or even just still being resident or the file locks in place). That would've been my first guess.
Can I suggest you try running a program called "Unlocker v1.8.5"
This runs in the background (in your system tray) - when you try to overwrite or delete a locked file - it provides you with some options as to how to deal with this, and what is "locking" the file.
I am quite sure, you will find these files are being held open by some other process - the fact all of these files together are being held open would indicate that the game / process is still active or resident in memory. Very rarely I have seen file handles remain open & locked even after the program no longer appears in the task list. In this case - anyones guess is as good as mine.
Hope that helps.