Hello dawnYNOV, if you are using the free trial, it is likely that being a trial will only allow you to work with small videos. You may also want to check the cache folder where the program saves the data during exporting. If this folder is full or too big it may prevent the program from exporting larger videos. To view where the program is saving the cache, you may open PhotoStage, click on Options > General > Cache and go to the folder path showing in the program and delete any files there that you don't need.