Before you download the installer package, you need to move the "RealCADD.app" out of any folder that it is in (it is probably in Applications >> RealCADD) and have it directly in Applications – i.e. not in a folder in Applications. This allows the installer package to update your existing RealCADD. If you want to keep a copy of the original RealCADD.app, probably the best way is simply to make a duplicate of the whole RealCADD folder – in Finder, select the folder and click File >> Duplicate (⌘D). Then drag the RealCADD.app out of the duplicate folder directly into the Applications folder. You can trash the rest of the duplicate folder.
Once you have downloaded RealCADD to your Mac, go to Finder >> Downloads and find the "RealCADD_Cocoa.pkg".
Double-click the package and follow the on-screen instructions to instal RealCADD.
Note: You may get a system message telling you that the "RealCADD_Cocoa.pkg" can't be opened because it is from an unidentified developer. Click the OK button. Then go to the Apple () menu >> System Preferences >> Security & Privacy >> General, where you will see at the bottom "RealCADD_Cocoa.pkg" was blocked from opening because it was not from an identified developer, together with a "Open Anyway" button. To continue with the installation you will need to hit the "Open Anyway" button. Whether you get these messages depends on your security settings and whether the current RealCADD version has been approved by Apple or not. Approval takes time, so the first release of a new version may not yet be approved.
The installer will update "RealCADD.app" in your Applications folder and update the "RealCADD" folder in your Documents folder. The RealCADD folder in Documents will contain the RealCADD library folder, the Scripts folder, an Examples folder and a read-me scripts PDF.
if you had the professional version of RealCADD and want to go on opening and exporting to DWG format, you will need to make a new folder in your Applications folder to contain the updated RealCADD.app and the RCADtoDWG file. See note at the bottom of the Home page for more details.
Navigate to your Applications folder (and into the new RealCADD folder if you have made one) and drag RealCADD.app to the dock to make an alias so you can start the program from the dock.
Tip: The installer will only update a RealCADD version lower than itself. So if you have been downloading intermediate beta versions, you will need to move an earlier version to the Applications folder to be updated. For example, if you have been using RealCADD 4.90b12, RealCADD 4.90 (which incorporates the bug fixes in the beta versions) will not update it – go back to 4.80 for updating. If you don't have an earlier version you will need to temporarily remove the whole RealCADD folder from Applications and store it on the Desktop.
Click the RealCADD icon in the dock to launch RealCADD.