Symbols changing when transferring to Oregon 450t from Basecamp on Mac

I am using the latest version of Mac OS (10.11.6) and latest version of BaseCamp for Mac (4.6.3) and just updated Oregon 450t to the latest avail. I am having trouble getting the Oregon to recognize the symbols used in BaseCamp when I transfer the files. I have 5 different standard symbols used in BaseCamp (not any special user created ones) but they all show up as the infamous blue flag when transferred up the the Oregon 450t. I've tried to save them to the SD card and to the internal memory on the Oregon. Any suggestions?