@IniBudi I didn’t make a video as the process is simple, and Cloudron 9.1 will take over soon. 
As @humptydumpty (thank you for stepping in) said, the process is guided.
Some important points :
- CCAI original version is dead : site now directs you to CustomAppGateway which is the new start point
- CustomAppGateway gives you choice of installing individual apps from there, or installing CCAI-P which is maybe more useful if installing multiple custom apps
- for individual installations, CustomAppGateway shows a catalogue, pick an item, popup shows a description and a curl one line installation command. Copy that and paste into your desktop/laptop terminal. It will :
- prompt for your Cloudron, e.g. my.domain.tld
- prompt for a token (create this in your Cloudron dashboard | Profile | Tokens
- prompt for app location, eg myapp.mydomain.tld
- invoke the installation : note that it will likely complete quickly but your Cloudron needs another couple minutes to install the app
- for multiple custom apps, use CustomAppGateway your install CCAI-P : same process as above.
- you will then have an app in your Cloudron which can install further apps (displays the same catalog as CustomAppGateway but no more curl download links)
- store your creds in /app/data
- pick an app and watch installation proceed
- wait for completion notice.
Note : your auth creds are now always input in your control (your desktop or your own Cloudron environment), never in a 3rd party site.
Let me know if any other questions