Looks amazing! I have several packs of Hex Kit tiles from different creators, are they easy to import and use with Hexxmap?
Yes, they are! You can copy them to the Content folder, either restart Hexxmap or press F6 to reload the content and they are available within the editor, although you have to set up the hex grid (dimensions etc.) once. If you want, you can have a look at the documentation, specifically this and this.