P.C. Tools Firewall/not accepting Avira Access

Good Morning ! P.C. Tools Firewall Plus wouldn't allow Avira access in its applications settings, it placed question marks next too all Avira processes,and when I clicked change to accept;a warning box stated that it would affect the Firewall's stealthing capabilities. Has anyone experienced this with the firewall,or is it a compatibility issue with Avira ? Note...I had two other Anti-Virus apps installed prior to installing Anti Vir Premium, and Firewall Plus had no issues with the previously installed apps. As an update the two previously installed apps weren't installed at the same time, just to clarify the previous sentence. Sincerely...Securon