It updates in the same way for all versions of Linux, just follow the instructions that are described.
Beta release, Linux shell installer.
A Java 8 runtime must be installed first using sudo apt-get install openjdk-8-jre or equivalent. Do not install a headless JRE, they lack audio I/O.
After downloading the installation file set permissions to allow it to run and install it as follows (example is for 5.19, filename varies according to the download):
5.19 linux_version
$ chmod +x REW_linux_version.sh
$ sudo ./REW_linux_version.sh
Start REW by running
$ roomeqwizard