Changes in architecture, especially on effects, may produce some backward incompatibility between 7.x and 8.x versions.
Upload your project and someone will be glad to check it out. Issues are usually resolved quickly. The PORTABLE project, not the export, is what's needed. Just follow instructions here...
http://nch.invisionzone.com/topic/23659-tips-for-getting-help-on-this-forum/
If it contains sensitive material link it in a personal message (PM). Click the envelope above. It won't be passed on or retained. Use FILE|SAVE PORTABLE PROJECT AS, not simply SAVE PROJECT, and don't forget to share it.