Please do not confuse USING, CONFIGURING and STYLING 3rd party extension!
Nothing (and certainly not a template) is preventing you to USE JPro Final Countdown module, if you have installed it correctly and assigned it to correct template position and menu item(s).
You can also CONFIGURE it as per varous available parameters in module's configuration back end in Joomla admin.
Now, STYLING it is another story, and that is what is documentation you mentioned reffering to. Changing module's visual appearance is what is Styling all about, and it is done by applying and adjusting certain CSS selectors. Using
.less files is just modern approach to good-old CSS styling, and if you are not pretty experienced in CSS, it might be more complicated and pretty frustrating.
You dont even have to follow JA documentation in order to change module's CSS selectors. Much easier is to, if you haven't already, create empty file
custom.css in folder
/templates/purity_iii/css/, then add to it any module-specific selector and adjust it to your liking.
Now, main question is how good are you with CSS, and that question is even more applicable for dealing with LESS.
From your comment I now realize that you need help with most basic actions in using Joomla, such as configuring module to appear on specific page. While I could recommend some great Tutorials, best of which are OSTraining Joomla 3 Classes, I am sure you can find 'em with a little help of your Google. So, I will list some basic steps for configuring this countdown module you want to show on front page.
- Go to
Extensions | Modules, find
JPro Final Countdown module, click on it to edit it.
Module tab set Position to
masthead and Status to
Published. Configure other fields as per your liking (Show Title to Hide, Welcome Text, etc...)
Menu Assignement tab choose
Only on the pages selected as module assignement, then click on
Select:None to clear all checkboxes first, and finally check only
Features Intro 2 menu item in
Main Menu|Layouts|New Layots menu, which is default menu item (Home item) in Purity III Quickstart.
Of course, if you have re-assigned default menu item, then select that item accordingly.
Save and Close button, and on front end you will see your module at the top of the page, right below toolbar. Please note that the following screenshot was made by adding
?tp=1 to show available module positions in template (after enabling that in
Extensions|Templates - Options buton ).
Now, there are many other things which can be done for configuring and styling this module, but these are just basic steps to make it visible.
Hope this helps.