Complex sentence: Innotek initially offered the application under a proprietary software license, making one version of the product available at no cost for personal or evaluation use, subject to the VirtualBox Personal Use and Evaluation License (PUEL).
Split into simpler sentences: Innotek initially offered the application under a proprietary software license. One version of the product was available at no cost for personal or evaluation use, subject to the VirtualBox Personal Use and Evaluation License (PUEL).