You also have to option of updating the KrPano version of your tour, but that has it's limits, as some or many of the flash components of your tour may no longer be supported. The best option is still to update to PTP2.
You would have to use the krpano update tool to update your krpano version : http://krpano.com/tools/kupdate/#top
Download the updater tool. For each project to update, add your TOUR.swf and swfobject/swfkrpano.js (and if needed krpanoiphone.js and krpanoiphone.license.js) into update list. Check 'Backup original files' to keep your old project files. And click 'Update krpano Viewer files'.
If the program asks you for license files, go into Panotour Pro 1.8 > Help > Licenses and Export them.