install tar.gz files in Slackware from SlackBuild.org, HELP

I need another lesson in installing packages that are in the .tar.gz form,

so....

In SlackBuild.org, there is a file I need for Coursera/Google to download a Windows instance of a RDP on my Linux box... they want me to "prove I know how to create a folder in Windows" on my Linux box... the RDP they "insist on using is a program called 'remmina'...this program is available on SlackBuild.org as a tar.gz - ONLY!

and that is where the problem starts...

~/Downloads$

~/Downloads$ dir
~/~/tar -xvf 'package-file-names'.tar.gz ...for each package

~/Downloads$ dir
~/~/Downloads$ 'package-file-names' & 'package-file-names'.tar.gz
#are both present at this point

~/Downloads$ configure 'package-file-names' ...doesn't work
~/Downloads$ make 'package-file-names' ...doesn't work
~/Downloads$ make-install 'package-file-names' ...doesn't work

so... I've downloaded 10 different 'package-file-name'.tar.gz and i can't get any of them to install and have no idea how to do it.

if it were a .tgz then, it would be
#upgradepkg --install-new 'package-file-name' ... right?

but, since 'remmina' comes in a gzipped tar ball, then it has to be
# configure 'package-file-name'
# make 'package-file-name'
# make-install 'package-file-name' ..... but, what if that won't work?

i am so lost ....
odin