Conformance to PDF 2.0 specification notes and tasks:

Section 1: OK
Section 2: OK
Section 3: OK
Section 4: OK
Section 5: OK
Section 6: OK

Section 7: Issues
 - 7.4.7 JBIG2 decoder ammendments 1 and 2 not implemented
 - 7.6.7 Unencrypted wrapper document not implemented
 - 7.10.2 Only linear interpolation for sampled function is performed

Section 8: Issues
 - 8.3.2.3 In user space, 1 / 72 inch is used, no UserUnit entry is used
 - 8.6.3 transfer functions and halftones are not used at all, color
   management system is used to convert colors
 - 8.6.5.6 No device to default color space is performed. Device color
   spaces can be set in color management system.
 - 8.6.5.8 default rendering intent is perceptual instead of relative colorimetric
 - 8.6.5.9 Black point compensation is user setting, graphic state setting
   is not respected (it is ignored)
 - 8.6.7 Overprint not implemented
 - 8.10.2 Some form dictionary entries, in table 93, are not all being processed
 - 8.10.4 Reference XObject is not supported. Instead, proxy is displayed.

Section 9: Issues
 - 9.3.2 Negative font size is not supported
 - 9.3.8 Text knockout not implemented
 - 9.5 Some type of fonts not supported yet (CIDFont, some others)
 - 9.6.2.1 Missing width is not used for missing characters
 - 9.6.4 d1 operator incorrectly doesn't ignore color/alpha operators
 - 9.7.4 CIDSystemInfo ignored in Table 115

Section 10: Issues
 - Color management system is used for color conversions. This can
   be turned of, and in that case, methods from 10.4.2 are used.
   Undercolor removal and black generation are not used.
 - 10.6 Halftoning is not implemented
 - 10.7.2 Flatness is ignored
 - 10.7.3 Smoothness is ignored
 - 10.7.5 Automatic stroke adjustment is ignored
 - 10.8 Separations are not produced
 - 10.8.3 Separation simulation is not performed

Section 11: Implemented partially
 - Transparency is not implemented in regular Qt's painter,
   but separate transparency renderer exist, which can render
   also spot colors

Section 12: Issues
 - 12.3.2.2 Destinations are used only to leap on specified page,
   position on page or fit hints are ignored
 - 12.3.5.2 File collection folders are ignored, files are
   displayed in a single list
 - 12.3.6 Navigator for file collections is ignored
 - 12.4.2 Page indices are used instead of labels
 - 12.4.4 Presentations are not implemented
 - 12.5.5 Annotation's transparency group is ignored
 - 12.5.6.3 Annotation's states are not implemented in viewer
 - 12.5.6.22 Watermark annotation - matrix and fixed print entry is not used
 - 12.6.3 Some trigger events are not executed or not implemented
 - 12.6.4 Some action are not executed in viewer
 - 12.6.4.8 URI actions doesn't use IsMap
 - 12.7.4.3 Variable text is implemented by Qt's QTextLayout
   and drawing, pdf's specific default appearance strings,
   and rich text is not implemented. This doesn't conform
   to PDF specification, but all unicode characters can be used.
 - 12.7.5.5 Signature field locking not implemented and signature
   seed dictionary is ignored
 - 12.7.6.2 Submit form action not implemented in viewer
 - 12.7.6.4 Import data action not implemented in viewer
 - 12.7.8 Form data format not implemented
 - 12.8 Modification detection using UR3/DocMDP method is not
   used, if signature is not valid, then it is not checked for
   modifications
 - 12.8 OCSP (Online Certificate Status Protocol) is not performed
 - 12.8.4 Long term validation of signatures not performed
 - 12.8.4.5 Validation data in custom VRI are not used, instead of them,
   validation data in DSS or embedded in the signature are used
 - 12.8.5 Document timestamp dictionary not implemented
 - 12.8.6 Permissions not implemented
 - 12.9 Measure feature not implemented
 - 12.10 Geospatial features not implemented

Section 13: Not implemented
 - Multimedia features not implemented (except some classes, which
   can read the data for multimedia - movies, sounds...)

Section 14: Issues
 - 14.3 Document metadata stream is not processed
 - 14.4 Modifiable file identifier is not updated
 - 14.5 Page-piece dictionaries not implemented
 - 14.9 Accessibility support not implemented
 - 14.10 Web capture not implemented
 - 14.11 Prepress support not implemented at all, only
   basic functionality works (media box, crop box, or,
   for example, reading output intents)
 - 14.12 Document parts not implemented

Annex F: Not implemented
 - Linearized PDF not implemented