You will have to be more specific. There are about 7000 extensions and probably an equal number of templates, each one in dozens of different versions, available for Joomla. We can't know off-hand how any of these dozens of thousands of software might work.
Which options in the Web Application Firewall did you have to disable to make the template work? If the only option you had to change was the tmpl= in the request we can add exceptions for specific tmpl parameters or completely disable that option.
As for the .htaccess Maker did you read its documentation on how to find out and apply exceptions?
If you cannot answer any of these questions please attach the template that's giving you trouble. Attachments are private, only you and us can see and download them. I will then install the template on a local development site to see what is being triggered, why and give you a preliminary security assessment of the template and the required workarounds.
Nicholas K. Dionysopoulos
Lead Developer and Director
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Please keep in mind my timezone and cultural differences when reading my replies. Thank you!