MQ4 protection, convert to dll

I need protection of a decompiled MQ4 expert advisor. As much parts of the script as possible should be converted into a dll, additionally protection of this dll and the remaining source code would be fine. The script would not be sold, but i need a binding of the script to certain computers and accounts, which should be changeable, no more than 10 accounts and/or computers. Also a restoring or variable names, that make sense within the script would be find but is not obligatory.