jignesh4 ,
Sorry that you are seeing issues with migration to MyEclipse.
1) We do not support shared libraries.You can use user libraries in MyEclipse. Right click on your project > Build path > Add Libraries. This would open Add Library wizard. You can select “User Library” and follow the wizard. These libraries get added to your project build path. These user libraries created can be added to any projects.
2) I am afraid we do not support importing of RAR files currently. For now you can extract the RAR file and import from the extracted location.
3) Also take a look at this document for detailed info on migration process :
http://www.myeclipseide.com/Blue/Rational_tool_migration.pdf
Sorry for the inconvenience caused.
Do let us know if you have any other issues.