As far as I know, trial for this application is approved after you contact the developers. However, it appears there is a direct download URL accessible on Software Informer page: http://bentley-microstation.software.informer.com/download/
Access the page and wait a little, the download will start automatically. I have downloaded and installed the package, and it had no viruses or any other kind of malware. If you look at the URL, you'll see it belongs to Bentely itself.