Critique of citation requested

Jo, let's walk through this in detail. You are arranging your data items in this format:

"Name of Database/Whatever," Creator of Database/Whatever, type of online item, Creator of Website, Name of Website (URL : date), type of record, date, book:page; citing ....

Meanwhile, the basic pattern for "Online Databases with Images" that you reference (3.16) calls for this:

Creator of Database, "Name of Database or Article," type of item, Creator of Website, Name of Website (URL : date), specific details ...

To dissect both:

• Name of Creator/Author traditionally goes before the title of whatever was created. It doesn’t matter what we’re citing—a book, an article, a database, a website, a map, a manuscript, or whatever—the basic rule is the same: We cite the creator, then we cite the title of whatever they created.
• At the website you are citing, there is not a database that carries the name "Frederick County, Land Records 1830-1831."
• "County Clerk," which you identify as the creator of the database (but is actually represents the county agency responsible for maintaining the record) is not affiliated with the website or with the Maryland State Archives. Therefore, it should not be cited in the part of the citation in which you identify the website. The county ID should be part of the citation to the original volume.

The fix:

When we cite original records from XYZ, for which images are published online at a website, we have two things to cite: (1) the original; and (2) the website that published the images.  We refer to these as two “layers" to the citation.

If you're using EE's 3d edition (2015) or 3d edition revised (2017) you should have a QuickStart Guide tipped into the front of the book. That gives you a very quick intro to "Layered Citations.” If you have an earlier edition without the QuickStart Guide, then you can find a discussion right here at EE’s website, in QuickLesson 19, “Layered Citations Work Like Layered Clothing.”

Specifically in this case, you need to first cite the local deed book:

Frederick County, Maryland, Deed Book 35: folio 382, Joseph Favorite to George Kuhn and Joseph Kuhn, Bill of Sale, 7 March 1831.

Notice that the citation starts with the largest element and works down to the smallest detail—i.e., County Government that Created the record > Name of Book > folio/page within the book > exact item on the page which you've chosen to describe in detail. by name of parties, type of item, and date.

After you’re done with citing the original record in Layer 1, then you’re ready to cite the website  in Layer 2.  We cite websites in the same format that we cite books. If we're citing a specific database at a website, then we cite it as though we're citing a chapter in a book.

In this case, we don’t have a database name. When we sign in at the website (using the URL you give) we are asked to “Select County.” When we select Frederick from the drop-down menu, then we have a form to fill in using the book:page citation or the name of the person or whatever.

This kind of website setup—one with no database title and a series of menu options to follow—is best cited it as we would a book, then (in the space normally used for the page number) cite the menu path that takes us to where we want to go. We bite the path by using greater than signs to link the menu items.

Maryland State Archives, MDLANDREC (https://mdlandrec.net : 25 January 2018) > Select County > Frederick.

The websites of most state archives (and other good providers) tell us how the book is identified in that facility.  We add that on as a third layer, prefaced by the word “citing …” or something similar.

Putting all three layers together (with semi-colons to mark the separation between layers) would give us this:

Frederick County, Maryland, Deed Book 35: folio 382, Joseph Favorite to George Kuhn and Joseph Kuhn, Bill of Sale, 7 March 1831; Maryland State Archives, MDLANDREC (https://mdlandrec.net : 25 January 2018) > Select County > Frederick; citing “Frederick County Court (Land Records) 1830–1831, JS 35, p. 0382, MSA CE 108-103.”

Notice two other things here:

1. When we copy exactly the way the provider identifies the record (as opposed to putting it in our own words), we put quotation marks around it.

2. This citation does not use your phrase "citing Record Group (RG) MSA CE 108-103." That is because the website is not actually citing "Record Group (RG) MSA CE 208-103." In fact, the assigned number, "CE 108-103," represents more than the record group.

If we query for "Maryland State Archives" +"Record groups" we'll get a link to a page that identifies the record groups at the archives (http://guide.mdsa.net/pages/viewer.aspx?page=indices#land). There if we put "CE 108" in the query box, we learn that this record group CE 108 (not CE 108-103) is the collection of Frederick County land records. The list then tells us that "103" is the item number within that record group.

This is a wonderfully instructive exercise that you've given us.

Actually I take that back - I did, or at least through the Department of Records and Information Services https://www1.nyc.gov/site/records/historical-records/order.page

So this is what I came up with.

City of New York Department of Health, New York State Certificate and Record of Birth certificate no. 3804 (1904), Arthur Knowles; NYC Records and Information Services, Municipal Archives, NYC ("https://www1.nyc.gov/site/records/historical-records/collections.page), PDF, issued December 2019. 

Eventide, did you intend for the message above to be on a page different from the one where the discussion began? If not, would you like for me to move your message and my response over to the thread?

In light of our discussion in the other thread, E's version would be this:

City of New York Department of Health, New York State Certificate and Record of Birth certificate no. 3804 (1904), Arthur Knowles; PDF obtained via NYC: Records & Information Services (https://www1.nyc.gov/site/records/historical-records/order.page : December 2019), "Order Historical Records" page.

The identification of website owner/creator and website title is what I see when I used your URL. Past that point, given that you accessed through the order page, EE would cite that page.