OS finally replied with the following instructions that fixed the driver problem for me;
Thank you for contacting Oregon Scientific Customer Support.
You can find the instructions for driver issues (Windows 8/10) here:
http://oregonscientific.se/index.php?option=com_fileman&view=file&folder=Program/WMR89&name=WMR89_SW_WIN10_UM_R0_151214.pdf&Itemid=888&lang=sv
I hope this is of some help for others in a similar predicament.