Thank you for your query.
I do apologizes for the inconveniences, here are the instructions on how to install DDNS manually:
1) Go to the following link: https://wiki.teltonika-networks.com/view/RUT955_Package_Downloads#Latest_Packages_.28from_07.00.29
2) Download the latest release under latest packages: 00.07.01 - Latest
3) Extract the package, there you will see all of the available services. For example DDNS service will be: DDNS.tar.gz
4) Go to routers WEBUI, navigate to Services -> Package Manager -> Upload -> click Browse -> Select the file, in my case I selected DDNS.tar.gz.
5) If you have done it correctly it should look like in this image:
Wait a couple of seconds, a new window will pop up similar to this:
6) Click proceed.
Regarding the CPU load issue on our newest firmware version this is a known bug. It displays the CPU load incorrectly on WEBUI. To find your true CPU load you would have to access your router via CLI and type the command: top , this command will show your true CPU load and in general in more detail.
Instructions on how to access CLI:
1) WebUI method: https://wiki.teltonika-networks.com/view/RUT955_CLI
2) Third party software Putty SSH access on Windows: https://wiki.teltonika-networks.com/view/Command_Line_Interfaces#Windows
If the issue regarding DDNS package reoccurs after following these instructions, could you please specify what exactly error you are receiving and post it here(possibly a screenshot). Many thanks.