I know more about the CSB program, but I can answer some of your questions about IBE.
(1) IBE is a joint business/engineering program. CSB is a joint business/computer science program. Both are jointly offered through the Lehigh Business and Engineering Schools.
(2) IBE typically takes either 4 or 5 years. After 4 years, you can graduate with a BS in Integrated Business and Engineering. This qualifies as a full (AACSB-accredited) business degree; however, it does not qualify as a full engineering degree (although it includes most of an engineering degree). If you stay for a 5th year, you can add a full (ABET-accredited) engineering degree, as a second degree.
CSB takes 4 years, and yields a BS in Computer Science and Business. This is only one degree, but it qualifies as both a full (AACSB-accredited) business degree and as a full (ABET-accedited) CS degree.
Don’t know about (3) and (4). IBE and CSB are really intense programs, and you should probably not expect to also squeeze in a traditional study abroad experience, unless you go in the summer. Lehigh has a summer program in Prague (the tech hub of eastern Europe) which is tailored for CSB students. Don’t know if there is something similar for the IBE students.