TRichView.com

1,2) TRichView tables are like HTML tables: column width and row heights are not explicitly defined. They are calculated basing on widths and height of cells. Apart from the cell content, the cell width is defined by BestWidth property, and the cell height is defined by BestHeight property.
See also ...

CanChange + Change must do the same work as inserting&deleting the character. And I do not understand how SetFocus affects to this problem.

You cannot call Screen.Free, because this method destroys the bitmap, but it still used by rvReport.
But I think you can call Dormant or FreeImage (as far as I understand how TBitmap works, only FreeImage makes sense here)

You cannot print a scaled document using TRVPrint. Use TRVReportHelper instead.

First, format RVReportHelper (Init + FormatNextPage).
Let PageWidth is a width specified in Init, PageHeight := RVReportHelper.GetLastPageHeight (I assume that the document has only one page).
Let DestRect is a ...

Yes, transparency is not supported directly. One of possible solutions is suggested by Michel.

Another solution.
It may be useful if you create a kind of report including TRichView objects. Draw the document into a metafile and display this metafile instead of TRichViewEdit. If you need an inplace ...

The best way to save data from TRichViewEdit in database is writing directly into the table field, instead of copying data to TDBRichViewEdit.
See the demo: Demos\Delphi\DB Demo\2 RichViewEdit\

Why the document is not updated when you call LoadRVFFromStream of TDBRichViewEdit? Because ...

Value of this property is interpreted by WinAPI. It is passed to SetTextCharacterExtra function.

I am afraid that you need to implement downloading data in your ActiveX yourself (using Indy, ICS or other components allowing to download data via http).

lkessler, I think that explanation does not explain too much

Added in to-do list: to add an option for saving named entities as character codes.
NBSP is not the only named character enity used.
Others are: GT, LT, AMP, and a number of characters for saving text of Symbol and Wingdings fonts.

Make sure that rvoClearTagOnStyleApp is excluded from EditorOptions

The Michel's suggestion is absolutely correct.
Call CanChange before (this will change table to the editing mode), and call Change after (this will inform table that RichViewEdit was modified).
All these operations are required only when you modify documents by non-editing methods (including ...

RvXML.SaveToStream

Can you give me a link to document explaining this issue?

It's a known problem, if you use version 1.9.8 and Delphi 2005.
If yes:
- if you are a registered TRichView version, update your copy of TRichView to the newer version;
- if you use a trial version, send me e-mail, I'll send you a fixed version.

One more suggestion: I just noticed that the TMediaPlayer's Stop button does not reset the movie position to the beginning (so I do not understand what's the difference between Stop and Pause buttons), so hiding additional buttons may be undesirable.