I’ve experienced it over time after time. TemplateMonster.com does not upgrade their template to work with latest ecommerce packages. This has been a real pain to most of web developers looking to use template monster designs for their osCommerce or Zen-cart projects. The worst thing is, there is no customer support team that can answer your questions at templatemoster.
I’ve worked on quite a lot of ecommerce websites that involve using TM templates. And 9 out of 10 times, I’ve faced misery and pain, begged for mercy and sacrificed time and money. The list is endless. All that I have learnt is, either never use TemplateMonster templates or charge extra for projects involving them.
The case is pretty much same with non-ecommerce templates. Flash templates require special softwares and low version of Adobe Flash. Killing.
If you are using TM templates, just make sure to allot more time and money than the advertised price.