That could be a hint as to why it causes a problem. Maximum protection configurations usually cause problems with other normal tasks, because less flexibility is provided in exchange for enhanced protection.
I'd do what @Stas suggests, try to make an exclusion for it and see it that helps. You can try lowering your protection to see if that will resolve the issue. On that note though, HitmanPro.Alert is known for causing software to break. If it didn't cause software to regularly break after updates often, then I'd probably be using it myself. Enterprises tend to update less so it likely is more convenient for them (Sophos owns the project now and they added it to their end-point protection).
If everything fails, then contact them with the e-mail provided by @plat1098. However, remember that by making exclusions, you do open more attack vectors for exploitation (e.g. if a media player was targeted) - even if you must. So be careful with what you exclude