At the time of writing this, the GrabCAD SolidWorks add-in is not supported for SolidWorks 2019. You will still be able to change and sync local files to GrabCAD projects, albeit less conveniently.
Before starting, make sure you have completed your installation of GrabCAD Workbench. If you have not, please finish the instructions here:
Upon being added to CalSTAR on GrabCAD, you'll be able to see all our projects.
In order to access these projects locally, first create a folder anywhere in your existing files. (When you downloaded GrabCAD, it by default should have created a "GrabCAD" folder in Documents.)
While the name of the folder does not matter, for clarity, you should name it with the same title as the GrabCAD project you are trying to sync to.
In the GrabCAD Desktop App, you'll have the option of manually connecting a project. Select that option, select a project, and link it to your recently created folder.
In the Desktop app, if you have successfully connected a project to your local folder, you'll be able to see the status of both the local folder and the online Workbench. If the Workbench panel is blue, that indicates that other people have made changes to files within the project and you will need to download these updates.
If the Workbench panel is black and not blue, you do not need to do anything and are completely up to date.
Hover your cursor over the Workbench panel and click to download.
Make sure all changed files are selected and click Download Selected. After all of the updates finish downloading, you should see a green box pop up both in the Desktop app and in the bottom right corner of your screen that says the downloads have finished.
To open a file for use with GrabCAD, click on the Open Folder button in the Local Folder panel, then double click on the desired part in the pop-up file browser. Other methods of navigating to the part are not guaranteed to work (although they may if your files are reasonably organized and you know for certain you are accessing a GrabCAD synced file).
Before working or making any changes to a file, first lock the part in the online GrabCAD Workbench by navigating to the part and right clicking. More documentation on locking can be found here.
If you do not lock the file you are working on, you may create file conflicts and lose changes!
Work on the file for as long as necessary. It is good practice to save and upload with every major revision, even if you will be working for quite a while on the same part.
It should not require SolidWorks crashing and you losing all your progress in order for you to learn the importance of saving often.
After saving the file with changes, we are now ready to upload. Save the file and return to the Desktop app. You should now see that the Local Folder panel is highlighted blue. Hover your cursor over the panel and click to upload.
In the upload tab, you will be prompted to include a comment describing the upload. Write a descriptive message detailing exactly what you have changed since the last version.
When you are done with this, press the Upload Selected button to complete the process (by default, all changed files should be selected). As before, a green box will pop up notifying you when the upload is done.
If you don't plan on making any more edits in the current session, go back to the online Workbench and unlock the file by right clicking.
You're all done. Again, make sure to unlock the file when you're all finished editing it!