Advanced configuration help you know how to config server, php version and more. For use this document. You need know a little PHP code and configuration server.
Edit config #
For edit config file. You need use FTP or File manager to open file from path:
OPC-4.x.x.x: Opencart root/extension/system/config/pdapp.php
OPC-3.x.x.x: Opencart root/system/config/pdapp.php
Permission writable #
Default we set CHMOD is 755. If my module still cannot write file. You can set: chmod to 777 to allow writable

Debug #
Default we set debug is false. If you want enable debug for check error. You can set: debug to true to enable debug.

Also, You can change prefix for folder encript of resources. Prefix default name is ‘prefix_‘. You can change to your string you want: prefix_ to your prefix_name
Note: You need change prefix before upload any files. Because after change prefix. Old files has path incorrect

Expired design #
Expired design is time auto clean data of user after design and out design or don’t add to cart. Default we set token of each design saved in 10 days. After 10 days. All files uploads, token and data design of a user will be removed from server. So, you can change time to remove design by code: token_date => your_date_number
Note: After expired design. If user still open design editor page. They can’t continue design and need reload for start design again.

Server configuration #
On this document. We only guide configuration with cpanel or via ftp. If your server using VPS or else. You need config by your self or ask your host support.
PHP version #
If your PHP version not suitable or you want upgrade. Please login your cpanel -> Software -> MultiPHP Manager -> Open

Continue, Select domain you want change (1) -> Select PHP version (2) -> Click Apply (3)
You can refer

Configurations #
To configurations PHP. You can login to Cpanel -> Software -> MultiPHP INI Editor -> Open

Continue, Select mode editor or UI mode -> Select domain you want change (1) -> Select Value (2) -> Click Apply.
Also, You can setup by file php.ini, .user.ini, .htaccess via ftp. Please refer

Permission writable #
To setup permission wriable for a folder. You need login Cpanel -> File manager -> Open & select folder want change -> Right mouse click (1) -> Click Change Permission (2) -> Select permission (3) -> Click Change Permissions (4)

Platform version #
You need use module version correctly with opencart version supported.