TRichView.com

Sorry, this feature is not planned in near future.
The simplest way to implement is using OnKeyDown, OnKeyPress, OnPaste to trap editing operations.
For example, the user pressed Backspace. You use OnKeyDown to prevent the default action, but apply the special style to the character to the left ...

Still in unknown future

Pass any TColor value and two nil s as additional parameters.
But there is a problem: cells do not support merging style collections.
That means that:
1) RVF file must have the same collection of styles as TRVStyle used by TRichView containing the table
2) RVFTextStylesReadMode and ...

Normally, width of cells are calculated basing on BestWidth properties of table cells. Consider assigning BestWidths properties from one table to another. There may be a problem with merged cells, or if cells in the same column have different BestWidths, though.

Widths of columns are stored in Fmt ...

a) Using paragraph and/or text protection (Options property of paragraph style, Protection property of text style)
or
b) Using table.OnCellEditing event

I confirm this problem. Will be fixed.

It's not possible to implement exactly what you want. You can include DeleteProtect without ModifyProtect, it's almost what you need, but... It does not allow the last character of item to be deleted, i.e. it does not allow to create empty item from it.
May be protection allowing making empty items ...

We will try to upload it in this week

Please wait for the next update, it must fix this problem

rvprModifyProtect does not allow editing text, so probably you should remove it.
rvprDeleteProtect does not allow deleting item (at least one character must remain), so this is probably what you need.
Also consider using rvprParaStartProtect.

No, there is only way: loading in offscreen TRichView and modifying paragraph properties. It is quite simple. But you need to decide what to do with list markers that can be in the document. Or what if it is started from table or break (they cannot be markered)

Try changing TCustomRVPrint.DrawPreview to: procedure TCustomRVPrint.DrawPreview(pgNo: Integer; Canvas: TCanvas;
const PageRect: TRect);
var OldMapMode, OldPPI: Integer;
OldWindowExt, OldViewportExt: TSize;
OldViewportOrg: TPoint;
begin
OldMapMode := GetMapMode(Canvas.Handle);
SetMapMode(Canvas ...

ItemPropRVFrm unit. Open this unit when RichViewActions package is an active project, otherwise you'll need to open other units (containing ancestor forms) before it.

If you use RichViewActions, call
rvActionNew1.ExecuteTarget(RVE);
when the application starts (in Form.OnCreate)

Preview100PercentWidth/Height just perform some calculations, they should not affect coordinates.
What is DrawTransparentPreview?