You can find Palm Desktop and other resource materials at the following link;
http://kb.hpwebos.com/wps/portal/kb/common/article/47831_en.html#tungstent5 I would suggest you do not sync. during the installation of PD. Once PD is installed, change the hotsync conduits to handheld overwrites desktop and sync. This will ensure that you are sync'ing fom the HH to the Desktop in order to not lose data from your T5. Once your data is restored into PD, use the export feature to backup your data from PD for disaster recovery. The best way to preserve your data is to export the data in each category in Palm Desktop to a seperate folder on your PC. Create a new folder on your PC somewhere that is convenient. Name it something like Palm Desktop Data. Click on the link below and follow the instructions on that page for the export procedure.
http://kb.hpwebos.com/wps/portal/kb2/common/article/28734_en.html Make sure you select all for the range in the export window. With the data saved in the folder you created, make a copy of that folder and save to a flash drive, cd-rw or external hard drive. Anytime you make a change in Palm Desktop, export the data that was changed to that folder and save again to the external media. With this process you can always import the data back into Palm Desktop anytime you have a problem with the data in Palm Desktop or if your computer/hard drive/device crashes.