Here is my best advise for a work around. Create a backup of your current Quickbooks company "currentcompany". Create a new QB company named "currentcompanymethod" (use your QB company name), use "currentcompanymethod" to link to your Method application . Continue using your original company for your live business. Create your Method application using the backed up company "currentcompanymethod". Once you have developed the Method application, create a new backup of "currentcompany". Then open "currentcompanymethod" and restore from backup the backup you just created from "currentcompany". This way you are only working with a backup file while you are developing your Method Application and then can bring over all of your current live data once you have got the Method application figured out.
Additional note. Always make a backup of your QB file before making major Method application changes.
This may not help the current situation, but may help others in the future.
Heather