Hi,
Which version of bw your using 3.x ot 7.x?
Activating from business content mean your just activating the structure of those objects.at BW side cubes/dso never have data as alone.
We need to load the data as per business needs.
HR data you can load form ECC to bw.
check and perform below points.
1. At source side, activate your data source at T - RSA5
2. Do the test run, source side T - RSA3. if you get data there then its fine.
3. Replicate data source into bw side and migrate data source to 7.x
4. Later you can install cube and transformations,info pack and dtp.
5. Once your data flow was active, you can start loading data into PSA by triggering info pack
6. By using dtp you can load data from PSA to your target.
Please be familiar will all bw concepts like Data modeling, Extraction and reporting.
You can search on google about the same.
Thanks