So sorry for your quandary. I have read that some, if not all Bernina embroidery machines will accept the .exp format.
Check your manual. I thought my Babylock would only accept .pes, but found that it will accept about 6 different formats.
Conversion programs will convert to .exp........none that I have found will convert to .art.......
Bernina wants you to buy from them. They make excellent sewing machines and probably embroidery machines, but their inflexibility to interface with other products sent me to Brother/Babylock.
Before downloading any software from any site, check with the site as to the capability of using their product with your brand and model of machine, not just the format. Once you purchase software, you own it and most, if not all merchants will not accept returns.