We do not give development training as such. But as you know QloApps is built is made on Prestashop. So you can use Prestashop dev docs to learn the development. And if you face any issues then please let us know.
Go to the backend, in that select “Setting” from “Hotel Reservation System” tab. Then you will be redirected to "Hotel General Configuration" page. In that page, scroll down to configuration, you will find Hotel Background Image, in that click on add file and select the image which you want to display.
Using the changes in the link will change the view, but you will need to make changes that are for image panel only, do not make changes that are not relevant to images panel.
The upgrade module will not clean the database, all the data created such as rooms, images, pricing, facilities, etc. will be saved.
The upgrade module will only discard the changes done in the code and add all the new features.
We are currently not using these templates. These templates were removed from Qloapps but are generated during installaion due to some issue, we have noted this issue and will be resolved in future version of QloApps.
If you want to use this module, you can get it from github as it is an opensource module from prestashop. Currently we do not provide support for this module but we will soon provide a module with similar features