DO NOT REMOVE THE DATA DIRECTORY JUST IN CASE!
First, dump your private keys using the dumpwallet command. You have to first unlock your wallet if your wallet is encrypted, and then run the following command in console. Remember to replace YOURUSERNAME with your actual username otherwise it won't work!
Win: dumpwallet "C:\Users\YOURUSERNAME\Desktop\dumpfile.txt"
Mac: dumpwallet "/Users/YOURUSERNAME/Desktop/dumpfile.txt"
Linux: dumpwallet "/home/YOURUSERNAME/Desktop/dumpfile.txt"
Then shut down the old wallet and rename your data directory to something like swiftcash.old maybe? Your data directory should be in the following path:
Win: %APPDATA%\SwiftCash
Mac: ~/Library/Application Support/SwiftCash
Linux: ~/.swiftcash
Then download the new wallet and run it. Now you need to use the importwallet command to import your private keys. Again, remember to replace YOURUSERNAME with your actual username otherwise it won't work!
Win: importwallet "C:\Users\YOURUSERNAME\Desktop\dumpfile.txt"
Mac: importwallet "/Users/YOURUSERNAME/Desktop/dumpfile.txt"
Linux: importwallet "/home/YOURUSERNAME/Desktop/dumpfile.txt"
That's it! You're good to go!
Keep in mind that in the new version, staking is not enabled by default. If you want to stake your coins, you need to add staking=1 in swiftcash.conf before you start the wallet.
For web wallet, if you used an email or password, you should be good. If you used a private key to login, you can convert your private key here. If you used a private key and then used the address of the other coins like Bitcoin, Litecoin and/or Dogecoin, you will need to use the old web wallet. You can download the old web wallet from Github to extract your keys.