TweakMASTER can be downloaded and evaluated for 30 days without obligation and without applying any registration code. It is designed to expire after a 30 day evaluation period. If you just installed it and shortly thereafter it shows as expired, this can be due to several possible causes.
Most probable cause would be that perhaps you installed it a while back and uninstalled it. Your system will remember it was installed previously and will only allow 30 days total evaluation period after the first day of the first installation. This is to prevent people from installing it, using it for 30 days, uninstalling it and then reinstalling it for another 30 days, and so on.
If this happens to you prematurely, let us know and we can extend your evaluation period temporarily.