We also take issue with how the textbox control handles page splits.  We
called into MS Support and ended up writing some text parsing logic.  It's
pretty darn rudimentary and I know it's fragile, but has worked for us so
far.

We use two textboxes instead of one and feed the text field to two methods
parasplit 1 and 2.  Fortunately we know the font, size and so on.  We have a
paragraph above that varies in how many lines it takes up.  We try count
these and feed in how many lines we have on page 1, how many characters fit
on a line, then we have logic for dealing with the fact that not all text
takes up a whole line (bulleted lists).  What we don't take care of is that
we are using a variable width font, so all this is adds up to quite a bit of
a gamble on where to split the page.

Expression for textbox1
=IIf(

CountRows("narrSchoolDescription") > 0,

CustAssembly.StaticMethods.ParaSplitFirst(

First(Fields!NarrativeText.Value, "narrSchoolDescription"),

32,

IIF(Parameters!ISSARC.Value = True, 9, 0), 100),
Code.rsLoc.GetResString("common_NoData"))

Expression for textbox2

=CustAssembly.StaticMethods.ParaSplitSecond(

First(Fields!NarrativeText.Value, "narrSchoolDescription"),

32,

IIF(Parameters!ISSARC.Value = True, 9, 0), 100)

Here's the code from the custom assembly.
public static string Crop(string input, int lines, int width)

{

int CropPoint = 0;

string[] TxtLines;

int LineCount = 0;

int MultiCount = 0;

System.Windows.Forms.TextBox TxtWordProcess = new
System.Windows.Forms.TextBox();

//validate parameters

System.Diagnostics.Debug.Assert(null != input);

if (null == input)

throw (new ArgumentException("input parameter is null"));

TxtWordProcess.Text = input;

TxtLines = TxtWordProcess.Lines;

foreach (string TxtLine in TxtLines)

{

if (LineCount < lines)

{

if (TxtLine.Length > width)

{

MultiCount = TxtLine.Length / width;

LineCount = LineCount + MultiCount;

if (LineCount < lines)

{

CropPoint = CropPoint + TxtLine.Length + 2;

}

}

else

{

CropPoint = CropPoint + TxtLine.Length + 2;

LineCount++;

}

}

}

if (CropPoint == 0)

{

if (input.Length < (width * lines))

{

CropPoint = input.Length;

}

else

{

CropPoint = (width * lines);

}

}

if (CropPoint > input.Length)

{

CropPoint = input.Length;

}

TxtWordProcess.Dispose();

return input.Substring(0, CropPoint);

}

public static string ParaSplitFirst(string Input, int TotLines, Int32
LinesUsed, int NumCharsPerLine)

{

string First = null;

string Second = null;

ParaSplit(Input, TotLines, LinesUsed, NumCharsPerLine, ref First, ref
Second);

return First;

}

public static string ParaSplitSecond(string Input, int TotLines, int
LinesUsed, int NumCharsPerLine)

{

string First = null;

string Second = null;

//ParaSplit(Input, TotLines, LinesUsed, NumCharsPerLine, ref First, ref
Second);

return Second;

}

public static void ParaSplit(string Input, int TotLines, int LinesUsed, int
NumCharsPerLine, ref string Output1, ref string Output2)

{

int CropMe = 0;

//validation

if (Input == null) { return; }

if (LinesUsed >= TotLines)

{

CropMe = 0;

}

else

{

CropMe = CropPoint(Input, TotLines - LinesUsed, 115);

}

Output1 = Input.Substring(0, CropMe);

Output2 = Input.Substring(CropMe, Input.Length - CropMe);

}

public static int CropPoint(string Input, int Lines, int NumCharsPerLine)

{

int CropPoint = 0;

string[] TxtLines;

int LineCount = 0;

int MultiCount = 0;

System.Windows.Forms.TextBox TxtWordProcess = new
System.Windows.Forms.TextBox();

//validate parameters

System.Diagnostics.Debug.Assert(null != Input);

if (null == Input)

throw (new ArgumentException("input parameter is null"));

TxtWordProcess.Text = Input;

TxtLines = TxtWordProcess.Lines;

foreach (string TxtLine in TxtLines)

{

if (LineCount < Lines)

{

if (TxtLine.Length > NumCharsPerLine)

{

MultiCount = TxtLine.Length / NumCharsPerLine;

LineCount = LineCount + MultiCount;

if (LineCount < Lines)

{

CropPoint = CropPoint + TxtLine.Length + 2;

}

}

else

{

CropPoint = CropPoint + TxtLine.Length + 2;

LineCount++;

}

}

}

if (CropPoint == 0)

{

if (Input.Length < (NumCharsPerLine * Lines))

{

CropPoint = Input.Length;

}

else

{

CropPoint = (NumCharsPerLine * Lines);

}

}

if (CropPoint > Input.Length)

{

CropPoint = Input.Length;

}

TxtWordProcess.Dispose();

return CropPoint;

}

public static int LineCount(string Input, int NumCharsPerLine)

{

int LineCount = 0;

int Count = 0;

string[] TxtLines;

System.Windows.Forms.TextBox TxtWordProcess = new
System.Windows.Forms.TextBox();

//validate parameters

System.Diagnostics.Debug.Assert(null != Input);

if (null == Input)

throw (new ArgumentException("input parameter is null"));

TxtWordProcess.Text = Input;

TxtLines = TxtWordProcess.Lines;

//Loop through each line, if the line wraps, check that it spills onto a
next line.

//if there isn't anything on the line, count that too.

foreach (string TxtLine in TxtLines)

{

Count = (TxtLine.Length / NumCharsPerLine);

LineCount += Count;

if (TxtLine.Length % NumCharsPerLine != 0)

{

LineCount++;

}

if (TxtLine.Length == 0)

{

LineCount++;

}

}

TxtWordProcess.Dispose();

return LineCount;

}

Steve MunLeeuw