If Otus seems to run extremely slow when you're building advanced assessments, you may want to check your school site's web filter/firewall (such as Securely) for potentially blocked URLs.
Some URLs that MUST be allowed by your firewall include:
Otus was built exclusively for K-12 by a group of former educators and administrators who are passionate about increasing the efficiency and effectiveness of educational technology. Otus is a web-based software solution with low barrier to entry from the technical requirements aspect. This article shares the minimal technical requirements. We have found that all schools have been able to provide these standards, unless they do not have Internet access.
-RAM: 1GB minimum
-Disk Space: None required
Other Specifications:-Internet access required
-Browser: Compatible with latest versions of Firefox, Chrome, Internet Explorer, and Safari
-Web plug-ins: No plug-ins required