Are you running Cubase 7 as an administrator? That's a very important and necessary step, without which jBridge simply won't work. Mine works fine. I keep my jbridged VST's in a folder called "jbridged VSTs" residing on the root of the c: drive.
Another important thing: your 32-bit VST's should NOT be located in the standard folder Cubase uses, but they need to be in a subfolder inside Program Files (x86). For the record, mine is called "32bit VSTs." Cubase should NOT be able to access that folder or conflicts between jBridge and VSTbridge may occur, resulting in Cubase crashing.
Incidentally, jBridge still works way better than Cubase's own VSTbridge. There are some very old VST's I still use that jBridge manages fine but VSTbridge can't handle without crashing Cubase. One example: the old Ueberschall Liquid Player. I don't use it often, but since I own virtually all the libraries (which cost me something like $2,000 back then) I don't want to lose it.
Desktop: i7 3770k, 32 GB RAM, nVidia GTX770 + GT640-DCSL fanless, 3 monitors (30" 2560x1600 + 2x 27" 1920x1080), 256 GB SSD (OS), 2 TB SATA III (audio), 3 TB SATA III (sample libraries), 3x 3 TB USB 3.0 (backup/archives), RME UFX, Win 8.1 Pro x64, Cubase 7.5, Sonar X3, Vienna Ensemble Pro 5.
Slaves: 2x i7 2700k, 16 GB RAM, 256 GB SSD, 3 TB SATA III, Win 8.1 Pro x64, Vienna Ensemble Pro 5.
Laptop: 17" HP EliteBook 8770w (i7 3820QM 2.7 Ghz/3.7 Ghz max OC, 16 GB RAM, 256 GB SSD, 1 TB SATA III), RME Babyface, Win 7 Pro x64, Vienna Ensemble Pro 5, Cubase 7.5, Sonar X3.