Correct, the Pre-Installation Wizard message is just letting you know it decided what the best thing to do would be. F-Lock is not really that important anymore. Maybe a few years ago it was important, but it is basically pretty much an obsolete feature at this point.
http://forum.ait-pro.com/forums/topic/php-fatal-error-cannot-redeclare-bpspro_ap_check/#post-21697
Are you saying your host cannot solve the server proxy routing configuration problem or is unwilling to fix the server proxy routing configuration problem in the link above. I have seen this exact same problem several times before and other folks host’s have fixed that problem. I do not think it is possible to create a workaround for that proxy routing mistake, but I am willing to give it another try. I give it about a 10% chance that I can figure out some kind of a workaround for that mistake. Send an email to info at ait-pro dot com with an administrator login to this website. The Plugin Firewall protects plugin files/scripts from being publicly accessible so it is an additional layer of security, but not nearly as important as AutoRestore|Quarantine so that would just mean that you would not have that additional layer of security.