Papyrus Designer is an extension of the Papyrus modeler. In order to install it, there are three different methods.
2. Install Papyrus Software designer via the market place].
3. Open the standard Eclipse installation dialog (Help->Install New Software).
Please note that Papyrus SW designer depends on CDT (C++ code generation feature) and JDT (Java code generation) which both require a Java VM 17 in recent Eclipse version. This implies that you cannot use this installation option, if your existing Eclipse installation ships with an embedded Java VM that is older or the installed Java in your system is older. This is currently the case for Papyrus RCPs older than 2023-03.
Papyrus vs. Papyrus SW designer versions
Papyrus SW Designer is an extension of Papyrus, but it is not part of the release train and released independently of Papyrus itself. Therefore, the version numbers differ.
Release 3.0.0 of SW Designer is compatible with Papyrus 6.0 and 7.0
Release 2.1.0 of SW Designer is compatible with Papyrus 5.0 and 6.0.
Release 2.0.0 of SW Designer is compatible with Papyrus 5.0 (for Eclipse version s 2021-03 and earlier)
A good starting point for Papyrus Designer are example models containing comments. These examples are available via File->New->Example, category "Papyrus" examples.