Hello rhol, Sethmaster is correct, though you can also use the old method if you wish. Do you have a screencap of the errors? Also, the spritesheet save greys itself out if you've chosen a maximum size too small to fit your images or if you try to save to the same directory as the original project. Try increasing the max size and if this doesnt work, can you please screencap the spritesheet dialog when the button is greyed so i can see ifI notice anything else or if it's a possible bug.
I tried the new method increasing the size so i can click ok but the animation doesn't show up.
I downloaded the old scml plugin and tried the old method and get this error:
Uncaught TypeError: Cannot read property 'length' of null
http://localhost:50000/Spriter_plugin.js, line 72 (col 37)