Import Photoshop Gradients ? The easiest way to bring in the presets is to use the import command (in the same way as the shapes command as well as the brushes and also the patterns and other preses). It is easy to use and can access a single GRD file as well as 100s of GRD files into the application. All you have to do is browse for the file. However, where is the panel in the first place ? You can find the panel in the window menu on the PC and mac. With the panel displayed, go to the right side menu and select the import and then browse for the files which can now be located anywhere on your machine though it is probably best to have a central location for them or perhaps even have them on your cloud drive. You can select multiple files or a single file and then click the open button.
They are in GRD format, I can't think of any other app that can read them outside of the Adobe products
If you don't have your old presets, you can quickly restore them by going to the right side menu and selecting the legacy command and that will bring back all your older presets. You will see them displayed in the legacy group and you can select and use them with all the standard features of the application. You can find the rainbow, blue, red, yellow etc presets.
On adding the presets to the application, you will notice that they are now in a group. So if you have brought in a GRD file marked as 'GX_Reds' say then the group will also be called that as well. You can expand the group and then see all the presets. If you bring in loads of GRD files, you will end up with lots and lots of groups. You can expand the groups and then select the individual presets and use them or move them to other groups or delete them etc. If you don't want the groupings then you can quickly remove them
One of my favorite features is the tools presets picker (TPL files). All the features of the preset can be saved to the tools presets. So if you have a preset made up of green and red and blue stops as well as transparency etc as well as having a blending mode set for the preset and transparency on along with opacity, method etc as well as a style all of that can be quickly saved for the tool to a tool preset by going to the top left corner and expanding out the tools presets (see below) and then go to the right side menu and click the drop down / gear settings and create a new preset which can be for that tool or just displayed with all the tools. As with all the presets, you can save the work to a file for future use and that is the format of TPL. If you delete the actual GRD preset it doesn't matter, this one still has it stored and you can quickly then apply the effect without having to remember the settings and the stops etc. Unfortunately, it doesn't seemed to have moved with the times and it is still using the load / replace approach
You can use the same menu command to add your GRD files to your application. Once you have added them, you can then group them, rename the groups, move the individual presets around, delete them and more and also drag them from the panel into the art board to add them as a layer
Once you have added all the presets you want and they can be in multiple groups in the latest release, you can select any number of them and then goto the right side menu of the panel and then go to the export selected and save it as a GRD file and once that has been done, you can access any of your favorites at any time or pass the file to a colleague who also uses the application and they / you can also again go to the right side menu and bring the file in via the method described above.