Hi Melanie thanks for posting in the Lucid Community! To clarify are you utilizing the Embed functionality as described in this Publish your Lucidchart document article? You mention it being spotty and difficult for your viewers to see - can you please clarify what the experience is here? Does the document fail to load or are you seeing an error message? If possible please share a screenshot of what you're seeing. 

Referring to the regular link - it sounds like you're using a sharable link (generated from the Sharing menu). Note that the sharing option you described - restriction to company-wide - means that only users who are on your corporate account can access it. Thus even if your viewers have a Lucid account and work at your organization if they aren't part of the main corporate account that you are they won't be able to access it. Could this be the case with your collaborators? 

If you prefer to share a link rather than embedding the document as a whole you might consider the Publishing feature (as described in that same Help Center article linked above). This allows you to publicly share your document without requiring the viewer to have a Lucid account.