These things do happen, and that’s why we have an all automated web site just for this purpose at support.showsize.com. Please login there with your contact email address that is on our file, and you should be able to get the latest installer download along with the license codes. This facility is free of charge for a year after your original purchase. After that the facility is renewed once you buy an upgrade. (For purchases earlier than Jan 22, 2010, the free upgrade period is 2 years)
How do you know if you have the latest version? Once you login at the above web site, you will see the latest version number. Please compare that with the one shown in Help–About box in ShowSize. You can also use the Updates menu in ShowSize to check for updates.