Upfront editing infuriating/unstable?

The concept behind Upfront (sic) is excellent and makes creating beautiful sites a lot less time-consuming. But am I the only Upfront user having a bad time? I have been through the tutorials that have been produced thus far and get them but my experience is far from what I see in those tutorials.

WordPress 4.2.2 / Upfront 0.2.6 / Spirit Theme 0.1.6 Site on 1&1 hosting being accessed over fibre broadband (79Mbps Down / 20Mbps Up)

All of these issues remain when I have experimented with different browsers (IE11, IE10, Safari, Chrome etc,.) and across multiple platforms (Win7, Win8.1 and Mac)

1) Elements jumping about

I am having problems with simple elements such as text boxes, refusing to be placed where I drag them within a section. There are no other elements nearby yet as soon as I drop the item it randomly hops elsewhere in the section. Dragging and delaying until the element ‘shadow’ catches up has no effect either.

2) Global header section. Element alignment ALWAYS goes to S*&^ within tablet/big tablet responsive layouts whenever I edit any other part of the layout, even outside of the responsive mode. Oddly mobile and ‘normal’ 1080px are unaffected.

3) Editing text – I add a text box and begin typing text. Maybe 5 or six words in – any new text begins appearing half way through an earlier word and there is NOTHING I can do to stop it. Clicking the cursor to the end of the sentence has no effect and any subsequent text doggedly pushes itself mid way through the earlier word. The only workaround I can find is typing the text into a editor like Notepad and pasting it into the box. God help me if I want to edit it after that, I have to re-paste the text and attempt to reapply all the CSS settings and formatting. ‘Double clicking’ the text to edit may or may not generate the edit menu above the text.

3) Lag in response. Particularly when opening the Upfront interface I experience several seconds of delay sometimes characterised by IE11 as “a delay caused by a long running script” other browsers stay quiet but nevertheless give me the delay.

As it stands Upfront is now causing me significant delays in finishing a customer site but I am too far into the design to abandon it.

Any suggestions??