SmartCrawl error log says:
[2019-05-27 14:37:39] We had an error communicating with [https://premium.wpmudev.org/api/seo-checkup/v1.1/emails]: (emails). [2019-05-27 17:33:20] Unable to obtain request arguments for [emails].
1) I cannot perform an SEO Checkout (without timing out). It'll run up to 99%, then kick out/timeout.
2) Every time I build a sitemap.xml, it says 1,000 URLs discovered, but no sitemap.xml is available
Initially, I could not run a sitemap scan. I noticed that the sitemap search problem came from having incorrect "post types" included in my wp_posts table. (oddly, the post "SLUG" was used in place of the post-type "post".) I'm not 100% certain, but I believe that these incorrect entries either came from AutoBlog or a WP All Import, that mismapped some of the terms & fields... somehow.
After I removed these posts types, (replacing the slug w/ "post") I was able to run the sitemap scan. But, even though I can see that URLs have been collected, they're still not entering into the sitemap.xml page (which shows as a blank page).