I'm currently evaluating AbsoluteTelnet and my feelings are mostly positive.
However there are some issues, which i would like to report there.
My environment: OS Windows XP, keyboard LK463 and custom keyboard layout dll crafted to generate VK codes for LK463 specific keys.
AbsoluteTelnet is simulating vt220 terminal. Translation is KOI8-R. Target host is OpenVMS 7.3.

First terminal simulation issues:

1) With translation turned on (at least KOI8-R) 8-bit control sequences handling becomes broken.
For example 8-bit CSI character is not interpreted as start of control sequence, but rendered as plain character.

2) Output of "ESC [ 1 x" or "ESC [ 0 x" makes AbsoluteTelnet crash.

Next keyboard mapping issues:

3) There are handy predefined text strings such as CMD-keypadplus, etc. Unfortunately they are incomplete. There is no such string for "keypad minus" key.
This key is documented on page 3-5 of "EK-VT220-RM-001" VT220 Programmer Reference Manual.

4) When mapping LK463 keys with non standard VKs (for example - 0x7c : F13, 0xe5 : F19) via "Edit keymap" facility - "This key" column gets "???" labels for such keys.
However, mapped key is working as expected. This minor inconvenience becomes annoying when several such keys are defined. Probably, key names should be not static, but fetched from some textual file?

5) After getting keyboard mapping for additional LK463 keys working as expected, I've decide to export mapping and move it to vt220.cskmp file.
To my surprise, those "???" keys denies to map in such way. I believe cskmp was modified correctly. Mapping for keys with standard VKs did function as expected.

If you need any additional information - ask freely.
And finally, my curiosity forces me to ask: do you plan to implement ReGIS, DECUDK and soft fonts support?

Checking....