If you'd like to use RayWare to close, cut, or otherwise fix your models and then use the STL files in another software, then you'll need to use the Export Tool. The Export Tool is a paid feature for Premium and Pro level software subscribers.
How to export
To export your model, begin by selecting your model. A selected model will be highlighted in blue. Once selected, press the wrench icon located in the center-left of your screen. Press the 'Export Selected' button, then choose the destination and name for your STL. Click 'Save'. Your model has now been exported as an STL.