Redmine

I can't test it now, my Redmine at work.

Some comments:
1. Comparing the diff's, I see in my pdf.rb line:
cv = issue.custom_values.detect {| v | ....
your version should be?:
cv = issue.custom_field_values.detect {| v | ....

2. Calculate the length of the text in my diff is based on the font page header. This is not correct. It almost does not affect the result, but leads to an increase in long columns of text. To correct this, use in def calc_col_width:
...
# by captions
pdf.SetFontStyle('B',8)
...
# by properties of issues
pdf.SetFontStyle('',8)
...
In this case, it may be necessary to add a constant of the column width for padding around the text, such as 5 mm.
col_padding = 5
col_width_min = query.columns.map {|v| pdf.GetStringWidth(v.caption) + col_padding}
...
x = pdf.GetStringWidth(w) + col_padding
...
n = pdf.GetStringWidth(v.rstrip) + col_padding
...
x = pdf.GetStringWidth(w) + col_padding

Please create a patch to the trunk.
I rebased your patch to the trunk.

I can make a patch only tomorrow at work.

About first row of second page ..
Change from (about line 333 in trunk):

          # make new page if it doesn't fit on the current one
          space_left = page_height - base_y - bottom_margin
          if max_height > space_left
            pdf.AddPage("L")
            base_x = pdf.GetX
            base_y = pdf.GetY
            render_table_header(pdf, query, col_width, row_height, col_id_width, table_width)
          end

To:

          # make new page if it doesn't fit on the current one
          space_left = page_height - base_y - bottom_margin
          if max_height > space_left
            pdf.AddPage("L")
            render_table_header(pdf, query, col_width, row_height, col_id_width, table_width)
            base_x = pdf.GetX
            base_y = pdf.GetY
          end

This should fix the result.

+1