I really want a linux based tool to operate my BCT15X, ideally something that could run on an outdated laptop or even a raspberry pi (so virtualized Windows program is out). I started testing bcprogtool-tcl in Debian, Centos, and Raspbian. So far, the program looks really good, the only issue is it appears to nolonger be under development. The Author's website is down, and the Google code site http://code.google.com/p/bcprogtool-tcl/ hasn't been updated since 2010. Hopefully a linux scanner enthusiast will be inspired to continue with the development.
More notes from playing with bcprogtool-tcl can be found on my bcprogtool-tcl notes page.
Although I don't have a BC125AT, this perl based software look good: bc125at-perl.
Got the software with a 'wget http://www.rikus.org/bc125at-perl-0.5.2.tar.gz'
To run it on Centos 6.8, had to enable the epel repo to install a perl module:
yum install 'perl(Device::SerialPort)'
Looks like Uniden publishes the protocol information for the BC125AT:
http://info.uniden.com/twiki/pub/UnidenMan4/BC125AT/BC125AT_PC_Protocol_V1.01.pdf
To program my ICOM IC-7000 radio, currently using CHIRP. Works well so far.
More notes and testing to come...